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1

Multicentre evaluation of the INTERPRET decision support system 2.0 for brain tumour classification.  

PubMed

In a previous study, we have shown the added value of (1) H MRS for the neuroradiological characterisation of adult human brain tumours. In that study, several methods of MRS analysis were used, and a software program, the International Network for Pattern Recognition of Tumours Using Magnetic Resonance Decision Support System 1.0 (INTERPRET DSS 1.0), with a short-TE classifier, provided the best results. Since then, the DSS evolved into a version 2.0 that contains an additional long-TE classifier. This study has two objectives. First, to determine whether clinicians with no experience of spectroscopy are comparable with spectroscopists in the use of the system, when only minimum training in the use of the system was given. Second, to assess whether or not a version with another TE is better than the initial version. We undertook a second study with the same cases and nine evaluators to assess whether the diagnostic accuracy of DSS 2.0 was comparable with the values obtained with DSS 1.0. In the second study, the analysis protocol was flexible in comparison with the first one to mimic a clinical environment. In the present study, on average, each case required 5.4?min by neuroradiologists and 9?min by spectroscopists for evaluation. Most classes and superclasses of tumours gave the same results as with DSS 1.0, except for astrocytomas of World Health Organization (WHO) grade III, in which performance measured as the area under the curve (AUC) decreased: AUC?=?0.87 (0.72-1.02) with DSS 1.0 and AUC?=?0.62 (0.55-0.70) with DSS 2.0. When analysing the performance of radiologists and spectroscopists with respect to DSS 1.0, the results were the same for most classes. Having data with two TEs instead of one did not affect the results of the evaluation. PMID:25042391

Julià-Sapé, Margarida; Majós, Carles; Camins, Àngels; Samitier, Alejandro; Baquero, Miguel; Serrallonga, Marta; Doménech, Sira; Grivé, Elisenda; Howe, Franklyn A; Opstad, Kirstie; Calvar, Jorge; Aguilera, Carles; Arús, Carles

2014-09-01

2

A multiresolution clinical decision support system based on fractal model design for classification of histological brain tumours.  

PubMed

Tissue texture is known to exhibit a heterogeneous or non-stationary nature; therefore using a single resolution approach for optimum classification might not suffice. A clinical decision support system that exploits the subbands' textural fractal characteristics for best bases selection of meningioma brain histopathological image classification is proposed. Each subband is analysed using its fractal dimension instead of energy, which has the advantage of being less sensitive to image intensity and abrupt changes in tissue texture. The most significant subband that best identifies texture discontinuities will be chosen for further decomposition, and its fractal characteristics would represent the optimal feature vector for classification. The performance was tested using the support vector machine (SVM), Bayesian and k-nearest neighbour (kNN) classifiers and a leave-one-patient-out method was employed for validation. Our method outperformed the classical energy based selection approaches, achieving for SVM, Bayesian and kNN classifiers an overall classification accuracy of 94.12%, 92.50% and 79.70%, as compared to 86.31%, 83.19% and 51.63% for the co-occurrence matrix, and 76.01%, 73.50% and 50.69% for the energy texture signatures; respectively. These results indicate the potential usefulness as a decision support system that could complement radiologists' diagnostic capability to discriminate higher order statistical textural information; for which it would be otherwise difficult via ordinary human vision. PMID:24962336

Al-Kadi, Omar S

2015-04-01

3

Brain tumour-associated status epilepticus.  

PubMed

We have reviewed the scant literature on status epilepticus in patients with brain tumours. Patients with brain tumour-associated epilepsy (TAE) appear less likely to develop status epilepticus (TASE) than patients with epilepsy in the general population (EGP) are to develop status epilepticus (SEGP). TASE is associated with lesions in similar locations as TAE; in particular, the frontal lobes. However, in contrast to TAE, where seizures commence early in the course of the disease or at presentation, TASE is more likely to occur later in the disease course and herald tumour progression. In marked contrast to TAE, where epilepsy risk is inversely proportional to Word Health Organization tumour grade, TASE risk appears to be directly proportional to tumour grade (high grade gliomas appear singularly predisposed). Whilst anti-epileptic drug (AED) resistance is more common in TAE than EGP (with resistance directly proportional to tumour grade and frontal location), TASE appears paradoxically more responsive to simple AED regimes than either TAE or SEGP. Although some results suggest that mortality may be higher with TASE than with SEGP, it is likely that (as with SEGP) the major determinant of mortality is the underlying disease process. Because all such data have been derived from retrospective studies, because TASE and SEGP are less common than TAE and EGP, and because TASE and SEGP classification has often been inconsistent, findings can only be considered preliminary: multi-centre, prospective studies are required. Whilst preliminary, our review suggests that TASE has a distinct clinical profile compared to TAE and SEGP. PMID:25150762

Goonawardena, Janindu; Marshman, Laurence A G; Drummond, Katharine J

2015-01-01

4

Identification of human brain tumour initiating cells  

Microsoft Academic Search

The cancer stem cell (CSC) hypothesis suggests that neoplastic clones are maintained exclusively by a rare fraction of cells with stem cell properties. Although the existence of CSCs in human leukaemia is established, little evidence exists for CSCs in solid tumours, except for breast cancer. Recently, we prospectively isolated a CD133+ cell subpopulation from human brain tumours that exhibited stem

Sheila K. Singh; Cynthia Hawkins; Ian D. Clarke; Jeremy A. Squire; Jane Bayani; Takuichiro Hide; R. Mark Henkelman; Michael D. Cusimano; Peter B. Dirks

2004-01-01

5

Neuropsychological Differences between Survivors of Supratentorial and Infratentorial Brain Tumours  

ERIC Educational Resources Information Center

Background: The purpose of this study is to evaluate the relationship between brain tumour location and core areas of cognitive and behavioural functioning for paediatric brain tumour survivors. The extant literature both supports and refutes an association between paediatric brain tumour location and neurocognitive outcomes. We examined…

Patel, S. K.; Mullins, W. A.; O'Neil, S. H.; Wilson, K.

2011-01-01

6

Telomerase activity in 144 brain tumours  

Microsoft Academic Search

Unlimited proliferation in immortalized cells is believed to be highly dependent on the activity of telomerase, a ribonucleoprotein that synthesizes telomeric repeats onto chromosome ends. Using a polymerase chain reaction-based telomeric repeat amplification protocol (TRAP) assay, we analysed telomerase activity in 99 benign and 45 malignant brain tumours. The TRAP assay results were quantitated by normalizing the telomerase activity of

T Sano; A Asai; K Mishima; T Fujimaki; T Kirino

1998-01-01

7

Imaging biomarkers in primary brain tumours.  

PubMed

We are getting used to referring to instrumentally detectable biological features in medical language as "imaging biomarkers". These two terms combined reflect the evolution of medical imaging during recent decades, and conceptually comprise the principle of noninvasive detection of internal processes that can become targets for supplementary therapeutic strategies. These targets in oncology include those biological pathways that are associated with several tumour features including independence from growth and growth-inhibitory signals, avoidance of apoptosis and immune system control, unlimited potential for replication, self-sufficiency in vascular supply and neoangiogenesis, acquired tissue invasiveness and metastatic diffusion. Concerning brain tumours, there have been major improvements in neurosurgical techniques and radiotherapy planning, and developments of novel target drugs, thus increasing the need for reproducible, noninvasive, quantitative imaging biomarkers. However, in this context, conventional radiological criteria may be inappropriate to determine the best therapeutic option and subsequently to assess response to therapy. Integration of molecular imaging for the evaluation of brain tumours has for this reason become necessary, and an important role in this setting is played by imaging biomarkers in PET and MRI. In the current review, we describe most relevant techniques and biomarkers used for imaging primary brain tumours in clinical practice, and discuss potential future developments from the experimental context. PMID:25520293

Lopci, Egesta; Franzese, Ciro; Grimaldi, Marco; Zucali, Paolo Andrea; Navarria, Pierina; Simonelli, Matteo; Bello, Lorenzo; Scorsetti, Marta; Chiti, Arturo

2015-04-01

8

Neuropathology and prognosis of foetal brain tumours  

Microsoft Academic Search

A survey of brain tumours that had been diagnosed prenatally by foetal sonography yielded 89 cases. The most commonly found\\u000a tumour entities were teratomas (53.9%), glioblastomas (14.6%), lipomas (9.0%), plexus papillomas (7.9%) and craniopharyngiomas\\u000a (5.6%). The mean gestational age at ultrasound diagnosis was 30.0 weeks, ranging between 25.4 weeks in craniopharyngiomas\\u000a and 35.3 weeks in lipomas. Girls were more frequently

Christian H. Rickert

1999-01-01

9

Equine nasal and paranasal sinus tumours. Part 1: review of the literature and tumour classification.  

PubMed

The normal gross and histological anatomy of the equine nasal and paranasal sinuses are reviewed and the relationships between the local anatomy, the occurrence of different tumour types, and of tumour spread are examined. The histological classification of the more common equine sinonasal tumours and tumour-like lesions are discussed. Clinical and pathological descriptions of 50 more recently recorded such tumours are separately tabulated. The literature shows that equine sinonasal tumours, both endemic and sporadic, are relatively uncommon in horses, with non-neoplastic growths such as maxillary (sinus) cysts, progressive ethmoid haematoma and inflammatory nasal polyps more commonly recorded. The equine paranasal sinuses, especially the caudal maxillary sinus, are the most common sites for sinonasal tumours and, in contrast to other species, primary nasal tumours are uncommon. The more common tumour types include squamous cell carcinoma that, in some cases, arise in the oral cavity and spread to the maxillary sinuses; adenocarcinomas; bone and dental tumours; fibrosarcomas and haemangiosarcomas. Except for some benign bone tumours, there are few records of successful treatment of equine sinonasal tumours. PMID:10328838

Head, K W; Dixon, P M

1999-05-01

10

Polyamine metabolism in brain tumours: diagnostic relevance of quantitative biochemistry  

PubMed Central

OBJECTIVE—Activation of polyamine metabolism is closely associated with cellular proliferation. The purpose was to investigate whether the content of the polyamines putrescine, spermidine, and spermine, and the activity of the first metabolic key enzyme of polyamine metabolism, ornithine decarboxylase (ODC), represent biochemical markers of malignancy in brain tumours.?METHODS—The concentration of putrescine, spermidine, and spermine, and the activity of ODC were biochemically quantified in tissue samples obtained during open microsurgery of 670 patients with brain tumours. Biochemical analysis and histopathological classification were carried out in serial tumour samples.?RESULTS—The activity of ODC was very low in peritumorous non-neoplastic brain tissue (0.9 (SD 0.6) nmol/g/h). It was significantly higher in gliomas and it significantly increased with a higher grade of malignancy (grade I 2.7 (2.8) nmol/g/h, grade II 3.1(4.0) nmol/g/h, grade III 5.7 (5.6) nmol/g/h, grade IV 10.6 (11.7) nmol/g/h). High enzyme activity was also found in medulloblastomas (25.5 (15.1) nmol/g/h), malignant lymphomas (52.1 (42.1) nmol/g/h), and metastases from carcinoma (14.9 (22.1) nmol/g/h). Lowest values were measured in epidermoid cysts (0.5 (0.2) nmol/g/h), craniopharyngiomas (1.2 (0.9) nmol/g/h), angioblastomas (1.6 (1.7) nmol/g/h), and neurinomas (2.0 (1.8) nmol/g/h). By contrast with ODC activity, polyamine concentrations did not correlate with the grade of malignancy. Correlation of regional biochemical and histomorphological data in rapidly growing neoplasms showed high enzyme activity in solid tumour parts and low activity in necrotic areas.?CONCLUSIONS—Novel data relating ODC activation and polyamine concentrations to neuropathology is presented indicating that high ODC activity represents a biochemical marker of malignancy in brain tumours. This information is important for clinical and therapeutic investigations.?? PMID:11413269

Ernestus, R; Rohn, G; Schroder, R; Els, T; Klekner, A; Paschen, W; Klug, N

2001-01-01

11

Combined texture feature analysis of segmentation and classification of benign and malignant tumour CT slices.  

PubMed

A computer software system is designed for the segmentation and classification of benign from malignant tumour slices in brain computed tomography (CT) images. This paper presents a method to find and select both the dominant run length and co-occurrence texture features of region of interest (ROI) of the tumour region of each slice to be segmented by Fuzzy c means clustering (FCM) and evaluate the performance of support vector machine (SVM)-based classifiers in classifying benign and malignant tumour slices. Two hundred and six tumour confirmed CT slices are considered in this study. A total of 17 texture features are extracted by a feature extraction procedure, and six features are selected using Principal Component Analysis (PCA). This study constructed the SVM-based classifier with the selected features and by comparing the segmentation results with the experienced radiologist labelled ground truth (target). Quantitative analysis between ground truth and segmented tumour is presented in terms of segmentation accuracy, segmentation error and overlap similarity measures such as the Jaccard index. The classification performance of the SVM-based classifier with the same selected features is also evaluated using a 10-fold cross-validation method. The proposed system provides some newly found texture features have an important contribution in classifying benign and malignant tumour slices efficiently and accurately with less computational time. The experimental results showed that the proposed system is able to achieve the highest segmentation and classification accuracy effectiveness as measured by jaccard index and sensitivity and specificity. PMID:23094909

Padma, A; Sukanesh, R

2013-01-01

12

[Anticonvulsant therapy for brain tumour-related epilepsy].  

PubMed

The lifetime risk of patients with brain tumours to have focal epileptic seizures is 20-80%. Based on current evidence the management of tumour-related seizures does not differ substantially from that applied to epilepsies from other aetiologies. Therefore, the choice of an anticonvulsant is based, above all, on tolerability and pharmacokinetic interactions with chemotherapeutic drugs. Levetiracetam is recommended by many authors as first-line therapy in brain tumour-related epilepsy; this corresponds with the recommendation of the German guidelines on the treatment of focal seizures of any aetiology. Based on current evidence, the prophylactic prescription of long-term antiepileptic drugs in brain tumour patients who have not presented with seizures is not justified. Because of the high risk of recurrence, however, antiepileptic treatment should be strongly considered after a single brain tumour-related seizure. PMID:25489755

Fröscher, W; Kirschstein, T; Rösche, J

2014-12-01

13

Brain MRI Classification using the Expectation Maximization  

E-print Network

Brain MRI Classification using the Expectation Maximization made a brain magnetic resonance image (MRI) classification algorithm that uses a twostage applied to a set of normal brain MR images for further testing. We accomplished a working

Chen, Tsuhan

14

Revised classification of neuroendocrine tumours of the lung, pancreas and gut  

Microsoft Academic Search

In this article new classifications of the neuroendocrine tumours of the lung, pancreas and gut are proposed. These classifications use a common frame work and attempt to consider the morphological, functional as well as biological features of the tumours.

C. Capella; P. U. Heitz; H. Höfler; E. Solcia; G. Klöppel

1995-01-01

15

Progression from first symptom to diagnosis in childhood brain tumours  

Microsoft Academic Search

This study was undertaken to investigate the evolution of clinical features between onset of symptoms and diagnosis in children\\u000a with brain tumours and to identify ways of shortening the time to diagnosis. One hundred and thirty-nine children with a brain\\u000a tumour were recruited from four UK paediatric neuro-oncology centres. Children had a median of one symptom or sign at symptom

Sophie Wilne; Jacqueline Collier; Colin Kennedy; Anna Jenkins; Joanne Grout; Shona Mackie; Karin Koller; Richard Grundy; David Walker

16

Towards drug discovery for brain tumours: interaction of kinins and tumours at the blood brain barrier interface.  

PubMed

Cancers of the brain are intrinsically more complicated to treat than systemic malignancies due to the unique anatomical features of the brain. The blood-brain barrier prevents chemotherapeutic agents from reaching brain neoplasms, and angiogenesis occurs as the metabolic needs of the tumour increase, thus further complicating treatment. The newly formed blood vessels form the blood-tumour barrier and are distinct from the blood-brain barrier in that they are more permeable. Being more permeable, these abnormal blood vessels lead to the formation of peri-tumoural edema, which is the cause of much morbidity and mortality associated with central nervous system neoplasms. While the cause of the increased permeability is unclear, kinins have been implicated in regulating the permeability of normal vasculature. Kinins are also known to exert many inflammatory actions affecting both normal and angiogenic blood vessels, as well as tumour cells. The vasodilatory and vascular permeabilizing effects of kinins, and particularly bradykinin and substance P, have been investigated with regard to delivery of chemotherapeutic agents to neoplastic brain tissue through both vascular barriers. In contrast, kinin receptor antagonists have been found to exert effects on tumour cells that result in decreased angiogenesis, tumour cell motility and growth. Thus, many recent patents describe kinin activity on brain vasculature, which may play an integral role in the development of treatments for malignancies in the central nervous system through amelioration of angiogenesis. In conjunction, patents that discuss the ability of kinins to decrease tumour cell migration and proliferation demonstrate that kinins may offer novel approaches to brain tumour therapy in the future. PMID:21073431

Harford-Wright, Elizabeth; Lewis, Kate M; Vink, Robert

2011-01-01

17

Using functional magnetic resonance imaging to plan surgical resections of brain tumours   

E-print Network

Brain tumours, even though rare, are one of the deadliest types of cancer. The five year survival rate for the most malignant type of brain tumours is below 5%. Modern medicine provides many options for treating brain ...

Gorgolewski, Krzysztof Jacek

2013-07-02

18

Cytokine Patterns in Brain Tumour Progression  

PubMed Central

Inflammation represents the immune system response to external or internal aggressors such as injury or infection in certain tissues. The body's response to cancer has many parallels with inflammation and repair; the inflammatory cells and cytokines present in tumours are more likely to contribute to tumour growth, progression, and immunosuppression, rather than in building an effective antitumour defence. Using new proteomic technology, we have investigated serum profile of pro- (IL-1?, IL-6, IL-8, IL-12, GM-CSF, and TNF-?) and anti-inflammatory cytokines (IL-4, IL-10), along with angiogenic factors (VEGF, bFGF) in order to assess tumoural aggressiveness. Our results indicate significant dysregulation in serum levels of cytokines and angiogenic factors, with over threefold upregulation of IL-6, IL-1?, TNF-?, and IL-10 and up to twofold upregulation of VEGF, FGF-2, IL-8, IL-2, and GM-CSF. These molecules are involved in tumour progression and aggressiveness, and are also involved in a generation of disease associated pain. PMID:23864770

Albulescu, Radu; Codrici, Elena; Popescu, Ionela Daniela; Mihai, Simona; Necula, Laura Georgiana; Petrescu, Daniel; Teodoru, Mihaela; Tanase, Cristiana Pistol

2013-01-01

19

Radiosurgery of the metastatic brain tumours with gamma-knife.  

PubMed

The results of treatment of metastatic brain tumours by radiosurgery are reported. Twenty cases including lung (11), colon (5), breast (1), ovary (1), liver cancer (1) and malignant melanoma (1) were involved. Seven cases had single and 13 had multiple brain metastases. In total 55 lesions were evaluated after radiosurgery with the gamma-knife. Following localization with MR1 and dose planning, radiosurgery with marginal doses between 12 to 25 Gy (mean 18.9 Gy) was delivered. In the follow-up studies with MRI after 3 months, 29 out of 55 (52.7%) lesions showed significant shrinkage. In contrast 25 showed either no change (17) or central necrosis (8), and one was enlarged. Thus the tumour control at 3 months was 98.2%, and subsequently 96.6% at 6 months. Clinical symptoms and signs were improved in most cases, but were aggravated in four cases either by tumour recurrence or by radiation-induced oedema. Although the tumours treated with radiosurgery were well controlled, tumour recurrence in another sites occurred in 4 case, of which 3 were treated by 2nd radiosurgery with 2 successful tumour control. Complications were generally mild and transient. In summary stereotactic radiosurgery is valuable new treatment not only for solitary metastases, but also for multiple or recurrent ones. PMID:7502736

Kida, Y; Kobayashi, T; Tanaka, T

1995-01-01

20

Current developments in radiotherapy for paediatric brain tumours  

Microsoft Academic Search

This review summarises current developments in radiation oncology and how they impact on the management of children with brain tumours. Improved understanding of radiobiology has led to attempts to improve the therapeutic ratio with hyperfractionated radiotherapy. Recent advances in planning and delivery of radiotherapy, including three-dimensional conformal radiotherapy, intensity modulated radiotherapy, and proton therapy allow a more precise localisation of

Roger E. Taylor

2006-01-01

21

Current approaches to the treatment of metastatic brain tumours  

PubMed Central

Metastatic tumours involving the brain overshadow primary brain neoplasms in frequency and are an important complication in the overall management of many cancers. Importantly, advances are being made in understanding the molecular biology underlying the initial development and eventual proliferation of brain metastases. Surgery and radiation remain the cornerstones of the therapy for symptomatic lesions; however, image-based guidance is improving surgical technique to maximize the preservation of normal tissue, while more sophisticated approaches to radiation therapy are being used to minimize the long-standing concerns over the toxicity of whole-brain radiation protocols used in the past. Furthermore, the burgeoning knowledge of tumour biology has facilitated the entry of systemically administered therapies into the clinic. Responses to these targeted interventions have ranged from substantial toxicity with no control of disease to periods of useful tumour control with no decrement in performance status of the treated individual. This experience enables recognition of the limits of targeted therapy, but has also informed methods to optimize this approach. This Review focuses on the clinically relevant molecular biology of brain metastases, and summarizes the current applications of these data to imaging, surgery, radiation therapy, cytotoxic chemotherapy and targeted therapy. PMID:24569448

Owonikoko, Taofeek K.; Arbiser, Jack; Zelnak, Amelia; Shu, Hui-Kuo G.; Shim, Hyunsuk; Robin, Adam M.; Kalkanis, Steven N.; Whitsett, Timothy G.; Salhia, Bodour; Tran, Nhan L.; Ryken, Timothy; Moore, Michael K.; Egan, Kathleen M.; Olson, Jeffrey J.

2014-01-01

22

The 2007 WHO Classification of Tumours of the Central Nervous System  

Microsoft Academic Search

The fourth edition of the World Health Organization (WHO) classification of tumours of the central nervous system, published\\u000a in 2007, lists several new entities, including angiocentric glioma, papillary glioneuronal tumour, rosette-forming glioneuronal\\u000a tumour of the fourth ventricle, papillary tumour of the pineal region, pituicytoma and spindle cell oncocytoma of the adenohypophysis.\\u000a Histological variants were added if there was evidence of

David N. Louis; Hiroko Ohgaki; Otmar D. Wiestler; Webster K. Cavenee; Peter C. Burger; Anne Jouvet; Bernd W. Scheithauer; Paul Kleihues

2007-01-01

23

Iodine-125 brachytherapy for brain tumours - a review  

PubMed Central

Iodine-125 brachytherapy has been applied to brain tumours since 1979. Even though the physical and biological characteristics make these implants particularly attractive for minimal invasive treatment, the place for stereotactic brachytherapy is still poorly defined. An extensive review of the literature has been performed, especially concerning indications, results and complications. Iodine-125 seeds have been implanted in astrocytomas I-III, glioblastomas, metastases and several other tumour entities. Outcome data given in the literature are summarized. Complications are rare in carefully selected patients. All in all, for highly selected patients with newly diagnosed or recurrent primary or metastatic tumours, this method provides encouraging survival rates with relatively low complication rates and a good quality of life. PMID:22394548

2012-01-01

24

Photodynamic assisted surgical resection and treatment of malignant brain tumours technique, technology and clinical application  

Microsoft Academic Search

Malignant brain tumours have a dismal prognosis with current state of the art technology. The main reasons for this lost battle in the battlefield of cancer are tumour cell invisibility to the surgical microscope and brain invasion. However, the vast majority of these tumours relapse locally making local radical removal the main strategy in their successful eradication. PDD and PDT

M. Sam Eljamel

2004-01-01

25

Brain tumours in Sweden 1996: care and costs  

PubMed Central

OBJECTIVES—Brain tumours cause considerable concern due to a high mortality and there are increasing efforts to provide adequate care, sometimes outside hospitals. Health care utilisation, direct costs of care, and the indirect social cost of morbidity and early mortality caused by brain tumours in Sweden in the year 1996 was analysed.?METHODS—Quantification of ambulatory care, care in hospital, long term and palliative/terminal care, drug consumption, temporary as well as long term morbidity, and mortality from comprehensive national data sources. Direct costs were calculated using 1996charges. Indirect costs were calculated by sex and age specific salaries. A sensitivity analysis considered the impact of alternative estimates of each item.?RESULTS—Indirect costs were 75% of the total and were caused mainly by early mortality. Direct costs were predominantly for care in hospital, long term care, and home health care. Among direct costs, astrocytomas III-IV and meningiomas accounted for 42% and 30% respectively.?CONCLUSIONS—The cost of illness from brain tumours reflects the characteristics of these malignancies. Despite their low incidence rate, the economic impact caused by high mortality among young persons is a predominant trait. Costs of acute hospital care and also long term care and home care are considerable.?? PMID:11080235

Blomqvist, P; Lycke, J; Strang, P; Tornqvist, H; Ekbom, A

2000-01-01

26

The diagnosis of brain tumours in children: a guideline to assist healthcare professionals in the assessment of children who may have a brain tumour  

Microsoft Academic Search

BackgroundBrain tumours are the commonest solid tumour in children. Children with brain tumours are frequently unwell for months prior to diagnosis. A prolonged period between symptom onset and diagnosis is associated with increased morbidity.ObjectiveTo develop an evidence-based clinical guideline to support healthcare professionals in the identification, assessment and investigation of children presenting with symptoms and signs that could be due

Sophie Wilne; Karin Koller; Jacqueline Collier; Colin Kennedy; Richard Grundy; David Walker

2010-01-01

27

Incidence of leukaemia and brain tumours in some "electrical occupations".  

PubMed Central

A 19 year follow up study was conducted to explore the association between occupations expected to be exposed to electromagnetic fields and the occurrence of leukaemia and brain tumours. Incidence of cancer between 1961-79 was calculated and the standardised morbidity ratio (SMR) with a 95% confidence interval (95% CI) was related to that of all Swedish working men. For all the selected "electrical occupations" the SMRs for total leukaemia and brain tumours were near unity. Increased risks were noted for all leukaemia among electrical/electronic engineers and technicians, (SMR 1.3; 95% CI 1.0-1.7) as well as in the sub-groups of telegraph/telephone (2.1; 1.1-3.6) and machine (2.6; 1.0-5.8) industries. Risk for chronic lymphoid leukaemia was increased in the same occupational category (1.7; 1.1-2.5) and in the sub-group of machine industry (4.8; 1.0-14.0), as well as for all linesmen (2.0; 1.0-3.5) and power linesmen (2.8; 1.1-5.7). Risk for acute myeloid leukaemia was increased among all miners (2.2; 1.0-4.1) and miners working in iron/ore mines (5.7; 2.1-12.4). Increased risk for all brain tumours (2.9; 1.2-5.9) and glioblastomas (3.4; 1.1-8.0) appeared among assemblers and repairmen in radio and TV industry. Raised risk for all brain tumours was seen for all welders (1.3; 1.0-1.7) and welders in iron/steel works (3.2; 1.0-7.4) and risk for glioblastomas was also increased for all welders (1.5; 1.1-2.1). No major changes in relative risk estimates were noted after the exclusion of persons who were over 65 at the time of diagnosis. Although a homogeneous pattern of increased risks of leukaemia or brain tumour was not noted, the hypothesis that magnetic fields might play a part in the origin of cancer cannot be rejected. PMID:1911402

Törnqvist, S; Knave, B; Ahlbom, A; Persson, T

1991-01-01

28

Functional MRI and intraoperative brain mapping to evaluate brain plasticity in patients with brain tumours and hemiparesis  

Microsoft Academic Search

OBJECTIVETo support the hypothesis about the potential compensatory role of ipsilateral corticofugal pathways when the contralateral pathways are impaired by brain tumours.METHODSRetrospective analysis was carried out on the results of functional MRI (fMRI) of a selected group of five paretic patients with Rolandic brain tumours who exhibited an abnormally high ipsilateral\\/contralateral ratio of activation—that is, movements of the paretic hand

F E Roux; K Boulanouar; D Ibarrola; M Tremoulet; F Chollet; I Berry

2000-01-01

29

Not all morning headaches are due to brain tumours.  

PubMed

Headaches causing early morning waking, or headaches which are more prominent on waking, always raise the suspicion of raised intracranial pressure, and hence the need for prompt evaluation to exclude the diagnosis of a brain tumour (particularly if they are associated with vomiting and papilloedema). However, there are many other much more common causes of "morning headache", both primary and secondary. As ever, history taking is key to the diagnosis. Attention to the possibility of analgesic medication overuse is particularly pertinent, but other treatable conditions such as depression and epilepsy must not be overlooked. PMID:19289557

Larner, A J

2009-04-01

30

Brain tumours under the age of three. The price of survival  

Microsoft Academic Search

Summary Between 1975 and 1989, 98 children with brain tumours under the age of three at time of diagnosis were entered into a retrospective study. Twenty of them are alive and free of tumour more than five years after treatment and were evaluated in this study. Thirteen tumour localizations were infratentorial and 7 were supratentorial. A histological examination was performed

E. Suc; C. Kalifa; R. Brauner; J. L. Habrand; M. J. Terrier-Lacombe; G. Vassal; J. Lemerle I

1990-01-01

31

Current developments in radiotherapy for paediatric brain tumours.  

PubMed

This review summarises current developments in radiation oncology and how they impact on the management of children with brain tumours. Improved understanding of radiobiology has led to attempts to improve the therapeutic ratio with hyperfractionated radiotherapy. Recent advances in planning and delivery of radiotherapy, including three-dimensional conformal radiotherapy, intensity modulated radiotherapy, and proton therapy allow a more precise localisation of the maximum dose region with maximum sparing of normal brain. Increasingly interactions between drugs and radiotherapy are exploited, but it is important to evaluate toxicity of combined modality therapy. The introduction of models to predict the impact of radiotherapy dose-volume parameters on long-term neuropsychological function will hopefully lead to further benefit with respect to sparing of normal tissue morbidity. PMID:16954052

Taylor, Roger E

2006-07-01

32

The postoperative brain tumour stem cell (BTSC) niche and cancer recurrence.  

PubMed

Currently, surgical resection is one of only a few options for treating brain cancer. Unfortunately, postoperative tumour recurrence remains almost inevitable despite additional radiation or chemotherapy treatment following resection. Clinical observations and a growing body of experimental evidence have led to speculation that there is a population of persistent brain tumour stem cells (BTSCs)--or brain tumour initiating cells--that are difficult to completely remove surgically. Furthermore, residual BTSCs following surgery may actually be more resistant to subsequent radiation and/or chemotherapies. It remains to be determined if brain surgeries render the postoperative tissue microenvironment more favourable for the survival and growth of BTSCs, and therefore the recurrence of brain tumours.We hypothesise that BTSC-based tumour recurrence may develop within a specific niche of the aberrant tumour microenvironment. Even when the gross appearance of the primary tumour seems confined, BTSCs (albeit accounting only for a small population of tumour cells) may microscopically enter the stroma, hampering curative surgeries. This article discusses the theory that surgical resection of brain tumours generates niches recruiting BTSCs to the surgical wounds, stimulating the proliferation and invasiveness of BTSCs, and leading to tumour recurrence. Postoperative brains are marked with active wound repair in peritumoural margins, which is likely to be accompanied by increased inflammatory paracrine production, angiogenesis and reactive astrogliosis. The postoperative BTSC niche concept is consistent with the observation that brain tumour recurrence usually occurs in tissues that are proximal to the resection margin. In this article, we intend to reflect recent advances that may lead to novel strategies to eliminate postoperative brain tumour recurrence. PMID:18463803

Liu, Jian-Min; Mao, Bo-Yong; Hong, Sun; Liu, Yan-Hui; Wang, Xiu-Jie

2008-05-01

33

Genomics and Metabolomics Research for Brain Tumour Diagnosis Based on Machine Learning  

E-print Network

Genomics and Metabolomics Research for Brain Tumour Diagnosis Based on Machine Learning Juan M biomedical technologies in the diagnosis and prognosis of cancer is changing medicine to an evidence-based diagnosis. We summarize some studies related to brain tumour research in Europe, based on the metabolic

34

Brain tumour and infiltrations dosimetry of boron neutron capture therapy combined with 252Cf brachytherapy.  

PubMed

This article presents a dosimetric investigation of boron neutron capture therapy (BNCT) combined with (252)Cf brachytherapy for brain tumour control. The study was conducted through computational simulation in MCNP5 code, using a precise and discrete voxel model of a human head, in which a hypothetical brain tumour was incorporated. A boron concentration ratio of 1:5 for healthy-tissue: tumour was considered. Absorbed and biologically weighted dose rates and neutron fluency in the voxel model were evaluated. The absorbed dose rate results were exported to SISCODES software, which generates the isodose surfaces on the brain. Analyses were performed to clarify the relevance of boron concentrations in occult infiltrations far from the target tumour, with boron concentration ratios of 1:1 up to 1:50 for healthy-tissue:infiltrations and healthy-tissue:tumour. The average biologically weighted dose rates at tumour area exceed up to 40 times the surrounding healthy tissue dose rates. In addition, the biologically weighted dose rates from boron have the main contribution at the infiltrations, especially far from primary tumour. In conclusion, BNCT combined with (252)Cf brachytherapy is an alternative technique for brain tumour treatment because it intensifies dose deposition at the tumour and at infiltrations, sparing healthy brain tissue. PMID:21705767

Brandão, Sâmia F; Campos, Tarcísio P R

2012-04-01

35

Guiding intracortical brain tumour cells to an extracortical cytotoxic hydrogel using aligned polymeric nanofibres  

NASA Astrophysics Data System (ADS)

Glioblastoma multiforme is an aggressive, invasive brain tumour with a poor survival rate. Available treatments are ineffective and some tumours remain inoperable because of their size or location. The tumours are known to invade and migrate along white matter tracts and blood vessels. Here, we exploit this characteristic of glioblastoma multiforme by engineering aligned polycaprolactone (PCL)-based nanofibres for tumour cells to invade and, hence, guide cells away from the primary tumour site to an extracortical location. This extracortial sink is a cyclopamine drug-conjugated, collagen-based hydrogel. When aligned PCL-nanofibre films in a PCL/polyurethane carrier conduit were inserted in the vicinity of an intracortical human U87MG glioblastoma xenograft, a significant number of human glioblastoma cells migrated along the aligned nanofibre films and underwent apoptosis in the extracortical hydrogel. Tumour volume in the brain was significantly lower following insertion of aligned nanofibre implants compared with the application of smooth fibres or no implants.

Jain, Anjana; Betancur, Martha; Patel, Gaurangkumar D.; Valmikinathan, Chandra M.; Mukhatyar, Vivek J.; Vakharia, Ajit; Pai, S. Balakrishna; Brahma, Barunashish; MacDonald, Tobey J.; Bellamkonda, Ravi V.

2014-03-01

36

Characterisation of tumour vasculature in mouse brain by USPIO contrast-enhanced MRI  

Microsoft Academic Search

To enhance the success rate of antiangiogenic therapies in the clinic, it is crucial to identify parameters for tumour angiogenesis that can predict response to these therapies. In brain tumours, one such parameter is vascular leakage, which is a response to tumour-derived vascular endothelial growth factor-A and can be measured by Gadolinium-DTPA (Gd-DTPA)-enhanced magnetic resonance imaging (MRI). However, as vascular

G. Gambarota; W. P. J. Leenders; C. Maass; P. Wesseling; B van der Kogel; O van Tellingen; A. Heerschap

2008-01-01

37

Combined radiotherapy and chemotherapy for high-grade brain tumours  

NASA Astrophysics Data System (ADS)

Glioblastoma (GBM) is the most common primary brain tumour in adults and among the most aggressive of all tumours. For several decades, the standard care of GBM was surgical resection followed by radiotherapy alone. In 2005, a landmark phase III clinical trial coordinated by the European Organization for Research and Treatment of Cancer (EORTC) and the National Cancer Institute of Canada (NCIC) demonstrated the benefit of radiotherapy with concomitant and adjuvant temozolomide (TMZ) chemotherapy. With TMZ, the median life expectancy in optimally managed patients is still only 12-14 months, with only 25% surviving 24 months. There is an urgent need for new therapies in particular in those patients whose tumour has an unmethylated methylguanine methyltransferase gene (MGMT) promoter, which is a predictive factor of benefit from TMZ. In this dissertation, the nature of the interaction between TMZ and radiation is investigated using both a mathematical model, based on in vivo population statistics of survival, and in vitro experimentation on a panel of human GBM cell lines. The results show that TMZ has an additive effect in vitro and that the population-based model may be insufficient in predicting TMZ response. The combination of TMZ with particle therapy is also investigated. Very little preclinical data exists on the effects of charged particles on GBM cell lines as well as on the concomitant application of chemotherapy. In this study, human GBM cells are exposed to 3 MeV protons and 6 MeV alpha particles in concomitance with TMZ. The results suggest that the radiation quality does not affect the nature of the interaction between TMZ and radiation, showing reproducible additive cytotoxicity. Since TMZ and radiation cause DNA damage in cancer cells, there has been increased attention to the use of poly(ADP-ribose) polymerase (PARP) inhibitors. PARP is a family of enzymes that play a key role in the repair of DNA breaks. In this study, a novel PARP inhibitor, ABT-888, is used in combination with both TMZ and radiation. The results show that ABT-888 significantly enhances TMZ and radiation cell killing, regardless of the MGMT status. In summary, the findings of this research demonstrate that the use of particle therapy and PARP inhibitors are particularly promising and might improve the treatment outcome in patients with GBM.

Barazzuol, Lara

38

Random Forest Classification for Training a Brain Computer Interface (BCI)  

E-print Network

Random Forest Classification for Training a Brain Computer Interface (BCI) Abstract1 Brain brain activity. Most3 existing BCIs detect specific mental activity in a so-called synchronous4 paradigm extraction7 followed by a classification scheme to detect intentions from the brain8 signal. In this paper

de Freitas, Nando

39

Non-negative matrix factorisation methods for the spectral decomposition of MRS data from human brain tumours  

PubMed Central

Background In-vivo single voxel proton magnetic resonance spectroscopy (SV 1H-MRS), coupled with supervised pattern recognition (PR) methods, has been widely used in clinical studies of discrimination of brain tumour types and follow-up of patients bearing abnormal brain masses. SV 1H-MRS provides useful biochemical information about the metabolic state of tumours and can be performed at short (< 45 ms) or long (> 45 ms) echo time (TE), each with particular advantages. Short-TE spectra are more adequate for detecting lipids, while the long-TE provides a much flatter signal baseline in between peaks but also negative signals for metabolites such as lactate. Both, lipids and lactate, are respectively indicative of specific metabolic processes taking place. Ideally, the information provided by both TE should be of use for clinical purposes. In this study, we characterise the performance of a range of Non-negative Matrix Factorisation (NMF) methods in two respects: first, to derive sources correlated with the mean spectra of known tissue types (tumours and normal tissue); second, taking the best performing NMF method for source separation, we compare its accuracy for class assignment when using the mixing matrix directly as a basis for classification, as against using the method for dimensionality reduction (DR). For this, we used SV 1H-MRS data with positive and negative peaks, from a widely tested SV 1H-MRS human brain tumour database. Results The results reported in this paper reveal the advantage of using a recently described variant of NMF, namely Convex-NMF, as an unsupervised method of source extraction from SV1H-MRS. Most of the sources extracted in our experiments closely correspond to the mean spectra of some of the analysed tumour types. This similarity allows accurate diagnostic predictions to be made both in fully unsupervised mode and using Convex-NMF as a DR step previous to standard supervised classification. The obtained results are comparable to, or more accurate than those obtained with supervised techniques. Conclusions The unsupervised properties of Convex-NMF place this approach one step ahead of classical label-requiring supervised methods for the discrimination of brain tumour types, as it accounts for their increasingly recognised molecular subtype heterogeneity. The application of Convex-NMF in computer assisted decision support systems is expected to facilitate further improvements in the uptake of MRS-derived information by clinicians. PMID:22401579

2012-01-01

40

Comparison of contrast in brightness mode and strain ultrasonography of glial brain tumours  

PubMed Central

Background Image contrast between normal tissue and brain tumours may sometimes appear to be low in intraoperative ultrasound. Ultrasound imaging of strain is an image modality that has been recently explored for intraoperative imaging of the brain. This study aims to investigate differences in image contrast between ultrasound brightness mode (B-mode) images and ultrasound strain magnitude images of brain tumours. Methods Ultrasound radiofrequency (RF) data was acquired during surgery in 15 patients with glial tumours. The data were subsequently processed to provide strain magnitude images. The contrast in the B-mode images and the strain images was determined in assumed normal brain tissue and tumour tissue at selected regions of interest (ROI). Three measurements of contrast were done in the ultrasound data for each patient. The B-mode and strain contrasts measurements were compared using the paired samples t- test. Results The statistical analysis of a total of 45 measurements shows that the contrasts in the strain magnitude images are significantly higher than in the conventional ultrasound B-mode images (P?brain tissue and glial tumour tissue than conventional ultrasound B-mode imaging. Ultrasound imaging of tissue strain therefore holds the potential of becoming a valuable adjunct to conventional intraoperative ultrasound imaging in brain tumour surgery. PMID:22621614

2012-01-01

41

Tissue Tracking: Applications for Brain MRI Classification  

PubMed Central

Bayesian classification methods have been extensively used in a variety of image processing applications, including medical image analysis. The basic procedure is to combine data-driven knowledge in the likelihood terms with clinical knowledge in the prior terms to classify an image into a pre-determined number of classes. In many applications, it is difficult to construct meaningful priors and, hence, homogeneous priors are assumed. In this paper, we show how expectation-maximization weights and neighboring posterior probabilities may be combined to make intuitive use of the Bayesian priors. Drawing upon insights from computer vision tracking algorithms, we cast the problem in a tissue tracking framework. We show results of our algorithm on the classification of gray and white matter along with surrounding cerebral spinal fluid in brain MRI scans. We show results of our algorithm on 20 brain MRI datasets along with validation against expert manual segmentations. PMID:24392193

Melonakos, John; Gao, Yi; Tannenbaum, Allen

2013-01-01

42

High intratumoural accumulation of stealth® liposomal doxorubicin (Caelyx®) in glioblastomas and in metastatic brain tumours  

PubMed Central

The blood–brain barrier is a major obstacle for the chemotherapeutic drugs to effectively reach primary or secondary brain tumours. Stealth® liposomal drugs are highly accumulated in tumoural tissues. In the present study we investigated the relative accumulation of99mTc-DTPA radiolabelled stealth® liposomal doxorubicin (Caelyx®) in 10 patients with metastatic brain tumours and five patients with brain glioblastoma undergoing radiotherapy. Patients with metastatic brain lesions were treated with 10 consecutive fractions of radiotherapy (whole brain, 3?Gy/fraction, day 1–12) followed by a booster dose of 9?Gy (3?Gy/fraction, day 21–23). Caelyx®, at a dose of 25?mg mg–2was given on day 1 and on day 21. Radiolabelled Caelyx® accumulation was 13–19 times higher in the glioblastomas and 7–13 times higher in the metastatic lesions, as compared to the normal brain. The drug accumulation in the tumoural areas was 40–60% of the accumulation in the bone marrow of the skull bones. The normal brain radioactivity was <4% of the bone marrow, confirming an important shielding effect of the blood–brain barrier in the normal but not in the tumoural tissue. Four of 10 patients with metastatic lesions showed a complete response in CT-scan performed 2 months following therapy. There was no severe toxicity related to radiotherapy or to chemotherapy noted. It is concluded that stealth® liposomal drugs selectively overcome the blood–brain barrier in the tumoural areas. The clinical importance of this observation is now under investigation. © 2000 Cancer Research Campaign PMID:11044350

Koukourakis, M I; Koukouraki, S; Fezoulidis, I; Kelekis, N; Kyrias, G; Archimandritis, S; Karkavitsas, N

2000-01-01

43

Diagnostic segregation of human brain tumours using Fourier-transform infrared and/or Raman spectroscopy coupled with discriminant analysis†  

PubMed Central

The most common initial treatment received by patients with a brain tumour is surgical removal of the growth. Precise histopathological diagnosis of brain tumours is to some extent subjective. Furthermore, currently available diagnostic imaging techniques to delineate the excision border during cytoreductive surgery lack the required spatial precision to aid surgeons. We set out to determine whether infrared (IR) and/or Raman spectroscopy combined with multivariate analysis could be applied to discriminate between normal brain tissue and different tumour types (meningioma, glioma and brain metastasis) based on the unique spectral “fingerprints” of their biochemical composition. Formalin-fixed paraffin-embedded tissue blocks of normal brain and different brain tumours were de-waxed, mounted on low-E slides and desiccated before being analyzed using attenuated total reflection Fourier-transform IR (ATR-FTIR) and Raman spectroscopy. ATR-FTIR spectroscopy showed a clear segregation between normal and different tumour subtypes. Discrimination of tumour classes was also apparent with Raman spectroscopy. Further analysis of spectral data revealed changes in brain biochemical structure associated with different tumours. Decreased tentatively-assigned lipid-to-protein ratio was associated with increased tumour progression. Alteration in cholesterol esters-to-phenylalanine ratio was evident in grade IV glioma and metastatic tumours. The current study indicates that IR and/or Raman spectroscopy have the potential to provide a novel diagnostic approach in the accurate diagnosis of brain tumours and have potential for application in intra-operative diagnosis. PMID:24098310

Gajjar, Ketan; Heppenstall, Lara D.; Pang, Weiyi; Ashton, Katherine M.; Trevisan, Júlio; Patel, Imran I.; Llabjani, Valon; Stringfellow, Helen F.; Martin-Hirsch, Pierre L.; Dawson, Timothy; Martin, Francis L.

2013-01-01

44

Second harmonic imaging: a new ultrasound technique to assess human brain tumour perfusion  

PubMed Central

Background: Second harmonic imaging is a new ultrasound technique that allows evaluation of brain tissue perfusion after application of an ultrasound contrast agent. Objective: To evaluate the potential of this technique for the assessment of abnormal echo contrast characteristics of different brain tumours. Methods: 27 patients with brain tumours were studied. These were divided into four groups: gliomas, WHO grade III–IV (n = 6); meningiomas (n = 9); metastases (n = 5); and others (n = 7). Patients were examined by second harmonic imaging in a transverse axial insonation plane using the transtemporal approach. Following intravenous administration of 4 g (400 mg/ml) of a galactose based echo contrast agent, 62 time triggered images (one image per 2.5 seconds) were recorded and analysed off-line. Time–intensity curves of two regions of interest (tumour tissue and healthy brain tissue), including peak intensity (PI) (dB), time to peak intensity (TP) (s), and positive gradient (PG) (dB/s), as well as ratios of the peak intensities of the two regions of interest, were derived from the data and compared intraindividually and interindividually. Results: After administration of the contrast agent a marked enhancement of echo contrast was visible in the tumour tissue in all patients. Mean PI and PG were significantly higher in tumour tissue than in healthy brain parenchyma (11.8 v 5.1 dB and 0.69 v 0.16 dB/s; p < 0.001). TP did not differ significantly (37.1 v 50.2 s; p = 0.14). A tendency towards higher PI and PG as well as shorter TP was apparent in malignant gliomas. When comparing different tumour types, however, none of these variables reached significance, nor were there significant differences between malignant and benign tumours in general. Conclusions: Second harmonic imaging not only allows identification of brain tumours, but may also help in distinguishing between different tumour types. It gives additional and alternative information about tumour perfusion. Further studies are needed to evaluate the clinical potential of this technique in investigating brain tumours—for example in follow up investigations of patients undergoing radiation or chemotherapy—especially in comparison with neuroradiological and neuropathological findings. PMID:12588918

Harrer, J; Mayfrank, L; Mull, M; Klotzsch, C

2003-01-01

45

Blood–brain barrier breakdown in septic encephalopathy and brain tumours*  

PubMed Central

Septic encephalopathy is associated with breakdown of the blood–brain barrier and cerebral oedema. These features are also common properties of brain tumours. Perimicrovessel oedema, disruption of associated astrocyte end feet and neuronal injury occur in a porcine model of acute septic encephalopathy. The adrenergic system has been implicated in the inflammatory response to sepsis and may play a role in controlling blood–brain barrier permeability, since the ?2-adrenoceptor agonist dopexamine inhibits perimicrovessel oedema formation whereas the ?1-adrenoceptor agonist methoxamine provokes it. Electron microscopy revealed tight junction opening in high-grade astrocytoma microvessels. Expression of the tight junction protein occludin is reduced in these microvessels and this reduction is inversely correlated with the degree of cerebral oedema. Normal astrocytes secrete factors that induce barrier properties in endothelial cells, whereas high-grade astrocytomas secrete vascular endothelial growth factor, which stimulates angiogenesis, down regulates occludin and increases endothelial cell permeability. The water channel protein aquaporin-4 is normally expressed in astrocyte foot processes around cerebral microvessels. Its expression is massively up-regulated in high-grade astrocytoma and around metastatic adenocarcinoma. There is a significant correlation between aquaporin-4 expression and the degree of cerebral oedema, but it is not clear whether increased aquaporin-4 expression enhances oedema formation or clearance. These results suggest that the pathophysiology of brain oedema is multifactorial, but that there may be common processes operating regardless of the aetiology. PMID:12162731

Davies, DC

2002-01-01

46

N -butyldeoxynojirimycin reduces growth and ganglioside content of experimental mouse brain tumours  

PubMed Central

Abnormalities in glycosphingolipid (GSL) biosynthesis have been implicated in the oncogenesis and malignancy of brain tumours. GSLs comprise the gangliosides and the neutral GSLs and are major components of the cell surface glycocalyx. N -butyldeoxynojirimycin (N B-DNJ) is an imino sugar that inhibits the glucosyltransferase catalysing the first step in GSL biosynthesis. The influence of N B-DNJ was studied on the growth and ganglioside composition of two 20-methylcholanthrene-induced experimental mouse brain tumours, EPEN and CT-2A, which were grown in vitro and in vivo. N B-DNJ (200??M) inhibited the proliferation of the EPEN and CT-2A cells by 50%, but did not reduce cell viability. The drug, administered in the diet (2400?mg kg?1) to adult syngeneic C57BL/6 mice, reduced the growth and ganglioside content of subcutaneous and intracerebral EPEN and CT-2A tumours by at least 50% compared to the untreated controls. N B-DNJ treatment also shifted the relative distribution of tumour gangliosides in accordance with the depletion of metabolic substrates. Side effects of N B-DNJ treatment were generally mild and included reductions in body and spleen weights and intestinal distension. We conclude that N B-DNJ may inhibit tumour growth through an effect on ganglioside biosynthesis and may be useful as a new chemotherapy for brain tumours. © 2001 Cancer Research Campaign http://www.bjcancer.com PMID:11308262

Ranes, M K; El-Abbadi, M; Manfredi, M G; Mukherjee, P; Platt, F M; Seyfried, T N

2001-01-01

47

Anatomical and biochemical investigation of primary brain tumours  

Microsoft Academic Search

Cancerous transformation entails major biochemical changes including modifications of the energy metabolism of the cell, e.g. utilisation of glucose and other substrates, protein synthesis, and expression of receptors and antigens. Tumour growth also leads to heterogeneity in blood flow owing to focal necrosis, angiogenesis and metabolic demands, as well as disruption of transport mechanisms of substrates across cell membranes and

Angelo Del Sole; Andrea Falini; Laura Ravasi; Luisa Ottobrini; Daniela De Marchis; Emilio Bombardieri; Giovanni Lucignani

2001-01-01

48

Local Kernel for Brains Classification in Schizophrenia  

NASA Astrophysics Data System (ADS)

In this paper a novel framework for brain classification is proposed in the context of mental health research. A learning by example method is introduced by combining local measurements with non linear Support Vector Machine. Instead of considering a voxel-by-voxel comparison between patients and controls, we focus on landmark points which are characterized by local region descriptors, namely Scale Invariance Feature Transform (SIFT). Then, matching is obtained by introducing the local kernel for which the samples are represented by unordered set of features. Moreover, a new weighting approach is proposed to take into account the discriminative relevance of the detected groups of features. Experiments have been performed including a set of 54 patients with schizophrenia and 54 normal controls on which region of interest (ROI) have been manually traced by experts. Preliminary results on Dorso-lateral PreFrontal Cortex (DLPFC) region are promising since up to 75% of successful classification rate has been obtained with this technique and the performance has improved up to 85% when the subjects have been stratified by sex.

Castellani, U.; Rossato, E.; Murino, V.; Bellani, M.; Rambaldelli, G.; Tansella, M.; Brambilla, P.

49

ADAPTIVE CLASSIFICATION OF MENTAL STATES FOR ASYNCHRONOUS BRAIN COMPUTER INTERFACES  

E-print Network

pathways of peripheral nerves and muscles". It measures signals coming directly from the brain, eitherADAPTIVE CLASSIFICATION OF MENTAL STATES FOR ASYNCHRONOUS BRAIN COMPUTER INTERFACES Jean Le Pavec.Clerc@sophia.inria.fr ABSTRACT Brain Computers Interfaces (BCI) are emerging as a new means of communication, aiming to make

Paris-Sud XI, Université de

50

Growth and puberty after growth hormone treatment after irradiation for brain tumours  

Microsoft Academic Search

The impact of treatment with either cranial or craniospinal irradiation with or without cytotoxic chemotherapy for a brain tumour distant from the hypothalamic-pituitary axis was assessed in 29 children who had reached final height. All had received growth hormone treatment for radiation induced growth hormone deficiency. Final height, segmental growth during puberty, and duration of puberty were studied. Both craniospinal

A L Ogilvy-Stuart; S M Shalet

1995-01-01

51

Radiobiological Response of Healthy and Tumour-Bearing Rat Brains To Synchrotron Microbeam Radiation  

Microsoft Academic Search

Microbeam radiation therapy (MRT) is an experimental radiotherapy concept that has been primarily developed for the treatment of malignant brain tumours. MRT uses high flux synchrotron x-rays delivered as an array of parallel microbeams in high doses of irradiation in fractions of seconds. The aims of this study were to 1) investigate the induction of bystander effects after normal and

Cristian Fernandez

2011-01-01

52

Evaluation of lactate detection using selective multiple quantum coherence in phantoms and brain tumours.  

PubMed

Lactate is a product of glucose metabolism. In tumour tissues, which exhibit enhanced glycolytic metabolism, lactate signals may be elevated, making lactate a potential useful tumour biomarker. Methods of lactate quantitation are complicated because of overlap between the lactate methyl doublet CH3 resonance and a lipid resonance at 1.3 ppm. This study presents the use of a selective homonuclear multiple quantum coherence transfer sequence (SelMQC-CSI), at 1.5?T, to better quantify lactate in the presence of lipids. Work performed on phantoms showed good lactate detection (49%) and lipid suppression (98%) efficiencies. To evaluate the method in the brain, the sequence was tested on a group of 23 patients with treated brain tumours, either glioma (N=20) or secondary metastases in the brain (N=3). Here it was proved to be of use in determining lactate concentrations in vivo. Lactate was clearly seen in SelMQC spectra of glioma, even in the presence of lipids, with high grade glioma (7.3 ± 1.9 mM, mean ± standard deviation) having higher concentrations than low grade glioma (1.9 ± 1.5 mM, p=0.048). Lactate was not seen in secondary metastases in the brain. SelMQC-CSI is shown to be a useful technique for measuring lactate in tumours whose signals are otherwise contaminated by lipid. PMID:25586623

Harris, L M; Tunariu, N; Messiou, C; Hughes, J; Wallace, T; DeSouza, N M; Leach, M O; Payne, G S

2015-03-01

53

Brain extraction based on locally linear representation-based classification.  

PubMed

Brain extraction is an important procedure in brain image analysis. Although numerous brain extraction methods have been presented, enhancing brain extraction methods remains challenging because brain MRI images exhibit complex characteristics, such as anatomical variability and intensity differences across different sequences and scanners. To address this problem, we present a Locally Linear Representation-based Classification (LLRC) method for brain extraction. A novel classification framework is derived by introducing the locally linear representation to the classical classification model. Under this classification framework, a common label fusion approach can be considered as a special case and thoroughly interpreted. Locality is important to calculate fusion weights for LLRC; this factor is also considered to determine that Local Anchor Embedding is more applicable in solving locally linear coefficients compared with other linear representation approaches. Moreover, LLRC supplies a way to learn the optimal classification scores of the training samples in the dictionary to obtain accurate classification. The International Consortium for Brain Mapping and the Alzheimer's Disease Neuroimaging Initiative databases were used to build a training dataset containing 70 scans. To evaluate the proposed method, we used four publicly available datasets (IBSR1, IBSR2, LPBA40, and ADNI3T, with a total of 241 scans). Experimental results demonstrate that the proposed method outperforms the four common brain extraction methods (BET, BSE, GCUT, and ROBEX), and is comparable to the performance of BEaST, while being more accurate on some datasets compared with BEaST. PMID:24525169

Huang, Meiyan; Yang, Wei; Jiang, Jun; Wu, Yao; Zhang, Yu; Chen, Wufan; Feng, Qianjin

2014-05-15

54

Photodynamic therapy of malignant brain tumours: a complementary approach to conventional therapies.  

PubMed

The poor outcome of primary malignant brain tumours is predominantly due to local invasion and local recurrence and their prognosis is highly dependent on the degree of resection. They have no border and, at best, a marginal zone that remains invisible to the surgeon. Photodynamic therapy (PDT) appears to be an interesting modality to fill the need for a targeted treatment that may reduce recurrence and extend survival with minimal side effects. In this review, we summarize the different technologies of brain tumour PDT employed such as interstitial PDT, and PDT-associated surgical resection, describing new light delivery devices. The role of dosimetry - one of the key factors behind successful brain tumour PDT - is discussed. This can be achieved by integrating results from in vivo studies. In this context, the development of new therapeutic photosensitizer delivery systems is also an area of significant research interest. Multifunctionality can be engineered into a single nanoplatform to provide tumour-specific detection, treatment, and follow-up. Such multitasking systems appear to be complementary to conventional technologies. PMID:22858248

Bechet, Denise; Mordon, Serge R; Guillemin, François; Barberi-Heyob, Muriel A

2014-03-01

55

Transient Global Amnesia and Brain Tumour: Chance Concurrence or Aetiological Association? Case Report and Systematic Literature Review  

PubMed Central

We report a patient presenting with episodes of transient amnesia, some with features suggestive of transient global amnesia (TGA), and some more reminiscent of transient epileptic amnesia. Investigation with neuroimaging revealed an intrinsic lesion in the right amygdala, with features suggestive of low-grade neoplasia. We undertook a systematic review of the literature on TGA and brain tumour. Fewer than 20 cases were identified, some of which did not conform to the clinical diagnostic criteria for TGA. Hence, the concurrence of brain tumour and TGA is very rare and of doubtful aetiological relevance. In some brain tumour-associated cases, epilepsy may be masquerading as TGA.

Milburn-McNulty, Phil; Larner, Andrew J.

2015-01-01

56

Meticulous classification using support vector machine for brain images retrieval  

Microsoft Academic Search

The objective of medical image retrieval system is to provide a tool for radiologists to retrieve the images similar to query image in content. Classification is an important part in retrieval system. This paper proposed a meticulous classification of MR-brain images using support vector machine (SVM). We used both texture and shape feature to express images, and then applied statistical

Weijuan Li; Zhentai Lu; Qianjin Feng; Wufan Chen

2010-01-01

57

Development of a positron probe for localization and excision of brain tumours during surgery  

NASA Astrophysics Data System (ADS)

The survival outcome of patients suffering from gliomas is directly linked to the complete surgical resection of the tumour. To help the surgeons to delineate precisely the boundaries of the tumour, we developed an intraoperative positron probe with background noise rejection capability. The probe was designed to be directly coupled to the excision tool such that detection and removal of the radiolabelled tumours could be simultaneous. The device consists of two exchangeable detection heads composed of clear and plastic scintillating fibres. Each head is coupled to an optic fibre bundle that exports the scintillating light to a photodetection and processing electronic module placed outside the operative wound. The background rejection method is based on a real-time subtraction technique. The measured probe sensitivity for 18F was 1.1 cps kBq-1 ml-1 for the small head and 3.4 cps kBq-1 ml-1 for the large head. The mean spatial resolution was 1.6 mm FWHM on the detector surface. The ?-ray rejection efficiency measured by realistic brain phantom modelling of the surgical cavity was 99.4%. This phantom also demonstrated the ability of the probe to detect tumour discs as small as 5 mm in diameter (20 mg) for tumour-to-background ratios higher than 3:1 and with an acquisition time around 4 s at each scanning step. These results indicate that our detector could be a useful complement to existing techniques for the accurate excision of brain tumour tissue and more generally to improve the efficiency of radio-guided cancer surgery.

Bogalhas, F.; Charon, Y.; Duval, M.-A.; Lefebvre, F.; Palfi, S.; Pinot, L.; Siebert, R.; Ménard, L.

2009-07-01

58

Diffusion tensor imaging demonstrates deviation of fibres in normal appearing white matter adjacent to a brain tumour  

Microsoft Academic Search

the objective was to study fibre orientation in the cerebral white matter of a patient with a brain tumour using diffusion tensor imaging (DTI). A patient with a mild left hemiparesis and a tumour in the right frontal lobe and 20 healthy volunteers were scanned with a DTI sequence. The scans were spatially normalised and the fibre orientation in the

U C Wieshmann; M R Symms; G J M Parker; C A Clark; L Lemieux; G J Barker; S D Shorvon

2000-01-01

59

Three validation metrics for automated probabilistic image segmentation of brain tumours  

PubMed Central

SUMMARY The validity of brain tumour segmentation is an important issue in image processing because it has a direct impact on surgical planning. We examined the segmentation accuracy based on three two-sample validation metrics against the estimated composite latent gold standard, which was derived from several experts’ manual segmentations by an EM algorithm. The distribution functions of the tumour and control pixel data were parametrically assumed to be a mixture of two beta distributions with different shape parameters. We estimated the corresponding receiver operating characteristic curve, Dice similarity coefficient, and mutual information, over all possible decision thresholds. Based on each validation metric, an optimal threshold was then computed via maximization. We illustrated these methods on MR imaging data from nine brain tumour cases of three different tumour types, each consisting of a large number of pixels. The automated segmentation yielded satisfactory accuracy with varied optimal thresholds. The performances of these validation metrics were also investigated via Monte Carlo simulation. Extensions of incorporating spatial correlation structures using a Markov random field model were considered. PMID:15083482

Zou, Kelly H.; Wells, William M.; Kikinis, Ron; Warfield, Simon K.

2005-01-01

60

[German guidelines for brain tumour imaging by PET and SPECT using labelled amino acids].  

PubMed

For the primary diagnosis of brain tumours, morphological imaging by means of magnetic resonance imaging (MRI) is the current method of choice. The complementary use of functional imaging by positron emitting tomography (PET) and single photon emitting computerized tomography (SPECT) with labelled amino acids can provide significant information on some clinically relevant questions, which are beyond the capacity of MRI. These diagnostic issues affect in particular the improvement of biopsy targeting and tumour delineation for surgery and radiotherapy planning. In addition, amino acid labelled PET and SPECT tracers are helpful for the differentiation between tumour recurrence and non-specific post-therapeutic tissue changes, in predicting prognosis of low grade gliomas, and for metabolic monitoring of treatment response. The application of dynamic PET examination protocols for the assessment of amino acid kinetics has been shown to enable an improved non-invasive tumour grading. The purpose of this guideline is to provide practical assistance for indication, examination procedure and image analysis of brain PET/SPECT with labelled amino acids in order to allow for a high quality standard of the method. After a short introduction on pathobiochemistry and radiopharmacy of amino acid labelled tracers, concrete and detailed information is given on the several indications, patient preparation and examination protocols as well as on data reconstruction, visual and quantitative image analysis and interpretation. In addition, possible pitfalls are described, and the relevant original publications are listed for further information. PMID:21789338

Langen, K-J; Bartenstein, P; Boecker, H; Brust, P; Coenen, H H; Drzezga, A; Grünwald, F; Krause, B J; Kuwert, T; Sabri, O; Tatsch, K; Weber, W A; Schreckenberger, M

2011-01-01

61

Li-Fraumeni syndrome: multiple distinct brain tumours in two brothers.  

PubMed

Li-Fraumeni syndrome is a rare autosomal dominant cancer-prone condition characterized by the occurrence of a large set of different types of cancer in a patient and their family. A germline disease-causing mutation of the gene encoding the p53 protein is associated with the syndrome. We report on a family in which segregation of a TP53 mutation in two generations was associated with two brain tumours, a leiomyosarcoma and a thyroid carcinoma in four male patients. The main patient presented with seizures revealing several primary brain tumours. We review recent views on its molecular basis and discuss management of the condition as well as a review of the literature. PMID:24636404

Lechien, J R; Brotchi, J; Van Maldergem, L; Costa de Araujo, P; Bruninx, G; Hilbert, P; Nubourgh, Y

2014-01-01

62

Brain connectivity hyper-network for MCI classification.  

PubMed

Brain connectivity network has been used for diagnosis and classification of neurodegenerative diseases, such as Alzheimer's disease (AD) as well as its early stage, i.e., mild cognitive impairment (MCI). However, conventional connectivity network is usually constructed based on the pairwise correlation among brain regions and thus ignores the higher-order relationship among them. Such information loss is unexpected because the brain itself is a complex network and the higher-order interaction may contain useful information for classification. Accordingly, in this paper, we propose a new brain connectivity hyper-network based method for MCI classification. Here, the connectivity hyper-network denotes a network where an edge can connect more than two brain regions, which can be naturally represented with a hyper-graph. Specifically, we first construct connectivity hyper-networks from the resting-state fMRI time series using sparse representation modeling. Then, we extract three sets of the brain-region specific features from the connectivity hyper-networks, and exploit a manifold regularized multi-task feature selection method to jointly select the most discriminative features. Finally, we use multi-kernel support vector machine (SVM) for classification. The experimental results demonstrate the efficacy of our proposed method for MCI classification with comparison to the conventional connectivity network based methods. PMID:25485444

Jie, Biao; Shen, Dinggang; Zhang, Daoqiang

2014-01-01

63

Pediatric brain tumours at a tertiary care hospital in Karachi.  

PubMed

The objectives of this study were to determine the epidemiology of brain tumors during infancy and childhood and to define and segregate childhood brain tumors vis-a-vis their morphological characteristics. The present study includes pediatric brain tumors, ICD-10 category C71 encountered during 10 years (January 1989 through December 1998) at a tertiary care hospital in Karachi. Eighty one cases were included, 58 (71.6%) in males and 23 (28.4%) in females with a male to female ratio of 2.5:1. The cases were divided into 3 age groups each covering five years of life (0-4, 5-9, 10-14 years), with the greatest number in the second age group i.e. 5-9 years followed by the third age group and the 0-4 year age group. The mean age for all cases, both genders was 8.8 years (95% CI 7.9; 9.6) with a marginal variation for cases occurring in the cerebrum and cerebellum. The malignancies occurred at a younger age in the males for each subcategory by site and morphology. The morphological distribution of cases was astrocytoma (28 cases, 34.6%), primitive neuroectodermal tumor or PNET (40 cases; 49.4%), ependymoma (8 cases, 10%), mixed glioma (4 cases; 5%) and a case of oligodendroglioma. The 81 malignancies included in this study were further categorized by site into two groups, supratentorial (27 cases; 33.3%) and infratentorial (54 cases; 66.7%). The morphological categorization of supratentorial tumors was astrocytoma (17 cases; 63%), ependymoma (5 cases; 18.5%), mixed glioma (2 cases; 7.4%). PNET with rhabdoid differentiation, oligodendroglioma and pinealoblastoma comprised 1 case (3.7%) each. The 17 supratentorial astrocytoma were sub-categorized as follows - pilocytic astrocytoma (5 cases; 29.4%), grade II astrocytoma (6 cases; 35.3%); grade III astrocytoma (2 cases; 11.8%), anaplastic astrocytoma (1 case; 5.9%) and glioblastoma multiforme (3 cases; 17.7%). The morphological categorization of infratentorial tumors was astrocytoma (11 cases; 20.4%), medulloblastoma (38 cases; 70.4%), ependymoma (3 cases; 5.6%) and mixed glioma - astroependymoma (2 cases, 3.7%). The morphological sub-categorization of infratentorial astrocytoma was pilocytic astrocytoma (7 cases, 63.6%), with gemistocytic astrocytoma, grade II, grade III and anaplastic astrocytoma comprising 1 (9.1%) case each. The morphological categorization of medulloblastoma was classical medulloblastoma (15 cases; 39.5%), desmoplastic medulloblastoma (8 cases; 21.1%), medulloblastoma with astrocytic differentiation (12 cases; 31.5%), medulloblastoma with neural differentiation (2 cases; 5.3%), and neuroblastic medulloblastoma (1 case; 2.6%). The pediatric brain tumors in Karachi reflect a developing country scenario, with a strong male predisposition and a late presentation with a peak in the 5-9 year age group. There is a predominance of medulloblastoma and a paucity of astrocytomas. The current study is a single institution study and needs cautious interpretation. Population-based studies are required to determine the cancer burden due to pediatric malignancies of the brain in this population and for the morphological categorization of brain tumors in Karachi. PMID:18159977

Ahmed, Naseem; Bhurgri, Yasmin; Sadiq, Saleem; Shakoor, Kazi A

2007-01-01

64

Alterations in the basal ganglia in patients with brain tumours may be due to excessive iron deposition  

PubMed Central

The accumulation of iron in the brain is a common physiological process. However, alterations in the deposition of iron or other paramagnetic substances are associated with various diseases. In the present study, the deposition of paramagnetic substances in patients with brain tumours was evaluated using T2 relaxometry. A total of 23 patients with untreated tumours or with recurrent tumours following treatment, together with a group of 19 age-matched healthy controls, were examined using T2 relaxometry at 3T. The relaxation times in the basal ganglia, thalamus and white matter were evaluated. Significantly lower T2 relaxation times were identified in the basal ganglia and thalamus of the patients with tumours, as compared with those of the controls (P<0.05). No statistically significant difference was identified between patients with untreated or recurrent brain tumours. The reduction in T2 relaxation times in the brain tumour patients was possibly caused by the accumulation of iron, since iron homeostasis is known to be altered in patients with tumours. We propose that increased iron deposition is a consequence of a higher risk of oxidative stress caused by an increased iron concentration in the plasma or cerebrospinal fluid. PMID:25435931

HERYNEK, VÍT; WAGNEROVÁ, DITA; MALUCELLI, ALBERTO; VYMAZAL, JOSEF; SAMEŠ, MARTIN; HÁJEK, MILAN

2015-01-01

65

Motor deficits correlate with resting state motor network connectivity in patients with brain tumours  

PubMed Central

While a tumour in or abutting primary motor cortex leads to motor weakness, how tumours elsewhere in the frontal or parietal lobes affect functional connectivity in a weak patient is less clear. We hypothesized that diminished functional connectivity in a distributed network of motor centres would correlate with motor weakness in subjects with brain masses. Furthermore, we hypothesized that interhemispheric connections would be most vulnerable to subtle disruptions in functional connectivity. We used task-free functional magnetic resonance imaging connectivity to probe motor networks in control subjects and patients with brain tumours (n?=?22). Using a control dataset, we developed a method for automated detection of key nodes in the motor network, including the primary motor cortex, supplementary motor area, premotor area and superior parietal lobule, based on the anatomic location of the hand-motor knob in the primary motor cortex. We then calculated functional connectivity between motor network nodes in control subjects, as well as patients with and without brain masses. We used this information to construct weighted, undirected graphs, which were then compared to variables of interest, including performance on a motor task, the grooved pegboard. Strong connectivity was observed within the identified motor networks between all nodes bilaterally, and especially between the primary motor cortex and supplementary motor area. Reduced connectivity was observed in subjects with motor weakness versus subjects with normal strength (P?brain tumours were followed longitudinally, and the subject who recovered showed reconstitution of her motor network at follow-up. The subject who was persistently weak did not reconstitute his motor network. Motor weakness in subjects with brain tumours that do not involve primary motor structures is associated with decreased connectivity within motor functional networks, particularly interhemispheric connections. Motor networks become weaker as the subjects become weaker, and may become strong again during motor recovery. PMID:22408270

Mikell, Charles B.; Youngerman, Brett E.; Liston, Conor; Sisti, Michael B.; Bruce, Jeffrey N.; Small, Scott A.; McKhann, Guy M.

2012-01-01

66

Oesophageal squamous cell carcinoma: relationship between fluorine-18 fludeoxyglucose positron emission tomography CT maximum standardised uptake value, metabolic tumour volume, and tumour, node and metastasis classification  

PubMed Central

Objectives We aimed to evaluate the relationships between primary tumour, maximum standardised uptake value, metabolic tumour volume and seventh edition American Joint Committee on Cancer (AJCC) classification in oesophageal squamous cell carcinoma (OSCC) patients. Methods Fluorine-18 fludeoxyglucose (18F-FDG) positron emission tomography (PET)-CT scans of 41 consecutive newly diagnosed OSCC patients were retrospectively reviewed. Maximum standard uptake value (SUVmax) and metabolic tumour volume (MTV) were recorded. Two-tailed Spearman's correlation was used to analyse the relationships between the metabolic parameters and the AJCC staging system. Results Positive correlations were observed between SUVmax, MTV and tumour (T) stage, in addition to node (N) stage and AJCC stage. Both metabolic parameters were independent variables that significantly affected the N stage and AJCC stage, and SUVmax was the only independent variable that significantly affected the T stage. Conclusion The metabolic parameters derived from 18F-FDG PET-CT were positively correlated with T, N and AJCC stage in primary OSCC. Our findings may suggest a complementary role of these parameters to seventh-edition AJCC staging in the prognostication of OSCC patients. PMID:22815420

Zhu, W-Q; Sun, X; Xing, L; Li, M; Yue, J; Qu, W; Sun, X; Kong, L; Yu, J

2012-01-01

67

Simple Fully Automated Group Classification on Brain fMRI  

SciTech Connect

We propose a simple, well grounded classification technique which is suited for group classification on brain fMRI data sets that have high dimensionality, small number of subjects, high noise level, high subject variability, imperfect registration and capture subtle cognitive effects. We propose threshold-split region as a new feature selection method and majority voteas the classification technique. Our method does not require a predefined set of regions of interest. We use average acros ssessions, only one feature perexperimental condition, feature independence assumption, and simple classifiers. The seeming counter-intuitive approach of using a simple design is supported by signal processing and statistical theory. Experimental results in two block design data sets that capture brain function under distinct monetary rewards for cocaine addicted and control subjects, show that our method exhibits increased generalization accuracy compared to commonly used feature selection and classification techniques.

Honorio, J.; Goldstein, R.; Honorio, J.; Samaras, D.; Tomasi, D.; Goldstein, R.Z.

2010-04-14

68

Brain metastasis in renal cancer patients: metastatic pattern, tumour-associated macrophages and chemokine/chemoreceptor expression  

PubMed Central

Background: The mechanisms of brain metastasis in renal cell cancer (RCC) patients are poorly understood. Chemokine and chemokine receptor expression may contribute to the predilection of RCC for brain metastasis by recruitment of monocytes/macrophages and by control or induction of vascular permeability of the blood–brain barrier. Methods: Frequency and patterns of brain metastasis were determined in 246 patients with metastatic RCC at autopsy. Expression of CXCR4, CCL7 (MCP-3), CCR2 and CD68+ tumour-associated macrophages (TAMs) were analysed in a separate series of 333 primary RCC and in 48 brain metastases using immunohistochemistry. Results: Fifteen percent of 246 patients with metastasising RCC had brain metastasis. High CXCR4 expression levels were found in primary RCC and brain metastases (85.7% and 91.7%, respectively). CCR2 (52.1%) and CCL7 expression (75%) in cancer cells of brain metastases was more frequent compared with primary tumours (15.5% and 16.7%, respectively; P<0.0001 each). The density of CD68+ TAMs was similar in primary RCC and brain metastases. However, TAMs were more frequently CCR2-positive in brain metastases than in primary RCC (P<0.001). Conclusion: Our data demonstrate that the monocyte-specific chemokine CCL7 and its receptor CCR2 are expressed in tumour cells of RCC. We conclude that monocyte recruitment by CCR2 contributes to brain metastasis of RCC. PMID:24327013

Wyler, L; Napoli, C U; Ingold, B; Sulser, T; Heikenwälder, M; Schraml, P; Moch, H

2014-01-01

69

Clinical and electroencephalographic data indicative of brain tumours in a seizure population.  

PubMed Central

One hundred and two patients suffering from seizures, with focal EEG signs (101 cases) and focal seizures but generalized EEG abnormalities (one case) were divided into tumour (twenty-one cases) and non-tumour (eighty-one cases) groups on the basis of contrast radiological studies. Retrospective analysis of various clinical data and EEG abnormalities, determined before the contrast radiological examinations, showed that the following were statistically significantly different between the two groups in favour of a tumoral aetiology for the seizures: age at onset of fits (greater than 20 years), presence of focal neurological signs and increased intracranial pressure, presence of focal unilateral delta waves without accompanying epileptic discharges, beta asymmetry between the cerebral hemispheres and hyperventilation-induced electrical seizures. A brain scan was a very useful screening test for the detection of a tumoral aetiology for seizures. PMID:625452

Vignaendra, V.; Ng, K. K.; Lim, C. L.; Loh, T. G.

1978-01-01

70

VIPARnd - GeVero® tool in planning of TPS scheduled brain tumour radiotherapy  

NASA Astrophysics Data System (ADS)

In this paper, VIPARnd - GeVero® tool is presented for the first time in an application to a brain tumour radiotherapy. Whereas usefulness of VIPARnd polymer gel in various radiotherapy techniques has recently been confirmed, GeVero® software for calculation of MRI polymer gel data and comparison with TPS dose distribution simulation is now examined. The results demonstrate satisfactory agreement between polymer gel dosimetry-MRI and TPS dose distributions and prove helpfulness of the software and VIPARnd polymer gel in radiotherapy dosimetry. It is also believed that the software facilitates data processing and therefore should be of further support in po-gel dosimetry studies.

Kozicki, Marek; Maras, Piotr; Rybka, Krzysztof; Biega?ski, Tadeusz

2009-05-01

71

Mathematical model of brain tumour with glia-neuron interactions and chemotherapy treatment.  

PubMed

In recent years, it became clear that a better understanding of the interactions among the main elements involved in the cancer network is necessary for the treatment of cancer and the suppression of cancer growth. In this work we propose a system of coupled differential equations that model brain tumour under treatment by chemotherapy, which considers interactions among the glial cells, the glioma, the neurons, and the chemotherapeutic agents. We study the conditions for the glioma growth to be eliminated, and identify values of the parameters for which the inhibition of the glioma growth is obtained with a minimal loss of healthy cells. PMID:25596516

Iarosz, Kelly C; Borges, Fernando S; Batista, Antonio M; Baptista, Murilo S; Siqueira, Regiane A N; Viana, Ricardo L; Lopes, Sergio R

2015-03-01

72

Image-guided microbeam irradiation to brain tumour bearing mice using a carbon nanotube x-ray source array  

NASA Astrophysics Data System (ADS)

Microbeam radiation therapy (MRT) is a promising experimental and preclinical radiotherapy method for cancer treatment. Synchrotron based MRT experiments have shown that spatially fractionated microbeam radiation has the unique capability of preferentially eradicating tumour cells while sparing normal tissue in brain tumour bearing animal models. We recently demonstrated the feasibility of generating orthovoltage microbeam radiation with an adjustable microbeam width using a carbon nanotube based x-ray source array. Here we report the preliminary results from our efforts in developing an image guidance procedure for the targeted delivery of the narrow microbeams to the small tumour region in the mouse brain. Magnetic resonance imaging was used for tumour identification, and on-board x-ray radiography was used for imaging of landmarks without contrast agents. The two images were aligned using 2D rigid body image registration to determine the relative position of the tumour with respect to a landmark. The targeting accuracy and consistency were evaluated by first irradiating a group of mice inoculated with U87 human glioma brain tumours using the present protocol and then determining the locations of the microbeam radiation tracks using ?-H2AX immunofluorescence staining. The histology results showed that among 14 mice irradiated, 11 received the prescribed number of microbeams on the targeted tumour, with an average localization accuracy of 454 µm measured directly from the histology (537 µm if measured from the registered histological images). Two mice received one of the three prescribed microbeams on the tumour site. One mouse was excluded from the analysis due to tissue staining errors.

Zhang, Lei; Yuan, Hong; Burk, Laurel M.; Inscoe, Christy R.; Hadsell, Michael J.; Chtcheprov, Pavel; Lee, Yueh Z.; Lu, Jianping; Chang, Sha; Zhou, Otto

2014-03-01

73

Image-guided microbeam irradiation to brain tumour bearing mice using a carbon nanotube X-ray source array  

PubMed Central

Microbeam radiation therapy (MRT) is a promising experimental and preclinical radiotherapy method for cancer treatment. Synchrotron based MRT experiments have shown that spatially fractionated microbeam radiation has the unique capability of preferentially eradicating tumour cells while sparing normal tissue in brain tumour bearing animal models. We recently demonstrated the feasibility of generating orthovoltage microbeam radiation with an adjustable microbeam width using a carbon nanotube based X-ray source array. Here we report the preliminary results from our efforts in developing an image guidance procedure for the targeted delivery of the narrow microbeams to the small tumour region in the mouse brain. Magnetic resonance imaging was used for tumour identification, and on-board X-ray radiography was used for imaging of landmarks without contrast agents. The two images were aligned using 2D rigid body image registration to determine the relative position of the tumour with respect to a landmark. The targeting accuracy and consistency were evaluated by first irradiating a group of mice inoculated with U87 human glioma brain tumours using the present protocol and then determining the locations of the microbeam radiation tracks using ?-H2AX immunofluorescence staining. The histology results showed that among 14 mice irradiated, 11 received the prescribed number of microbeams on the targeted tumour, with an average localization accuracy of 454 ?m measured directly from the histology (537 ?m if measured from the registered histological images). Two mice received one of the three prescribed microbeams on the tumour site. One mouse was excluded from the analysis due to tissue staining errors. PMID:24556798

Zhang, Lei; Yuan, Hong; Burk, Laurel M; Inscoe, Christy R; Hadsell, Michael J; Chtcheprov, Pavel; Lee, Yueh Z; Lu, Jianping; Chang, Sha; Zhou, Otto

2014-01-01

74

77 FR 16925 - Medical Devices; Neurological Devices; Classification of the Near Infrared Brain Hematoma Detector  

Federal Register 2010, 2011, 2012, 2013, 2014

...Devices; Classification of the Near Infrared Brain Hematoma Detector AGENCY: Food and Drug...is classifying the Near Infrared (NIR) Brain Hematoma Detector into class II (special...the generic name Near Infrared (NIR) Brain Hematoma Detector, and it is...

2012-03-23

75

Classification and controversies in pathology of ependymomas  

Microsoft Academic Search

Purpose  Bailey and Cushing established ependymoma as a brain tumour entity in the first brain tumour classification (1926). Diagnosis\\u000a of ependymomas is not subject to controversy as long as other tumours presenting ependymoma-like features have been ruled\\u000a out. Grading conversely is a source of debate. Description of histological features establishing diagnosis and grading of\\u000a ependymomas may help to better understand this

Catherine Godfraind

2009-01-01

76

Long-term supratentorial brain structure and cognitive function following cerebellar tumour resections in childhood.  

PubMed

The cerebellum is connected to extensive regions of the cerebrum, and cognitive deficits following cerebellar lesions may thus be related to disrupted cerebello-cerebral connectivity. Moreover, early cerebellar lesions could affect distal brain development, effectively inducing long-term changes in brain structure and cognitive function. Here, we characterize supratentorial brain structure and cognitive function in 20 adult patients treated for cerebellar tumours in childhood (mean age at surgery: 7.1 years) and 26 matched controls. Relative to controls, patients showed reduced cognitive function and increased grey matter density in bilateral cingulum, left orbitofrontal cortex and the left hippocampus. Within the patient group, increased grey matter density in these regions was associated with decreased performance on tests of processing speed and executive function. Further, diffusion tensor imaging revealed widespread alterations in white matter microstructure in patients. While current ventricle volume (an index of previous hydrocephalus severity it patients) was associated with grey matter density and white matter microstructure in patients, this could only partially account for the observed group differences in brain structure and cognitive function. In conclusion, our results show distal effects of cerebellar lesions on cerebral integrity and wiring, likely caused by a combination of neurodegenerative processes and perturbed neurodevelopment. PMID:25665770

Moberget, T; Andersson, S; Lundar, T; Due-Tønnessen, B J; Heldal, A; Endestad, T; Westlye, L T

2015-03-01

77

Brain and ocular metastases from a transmissible venereal tumour in a dog.  

PubMed

A five-year-old crossbred dog was referred with rapidly growing masses over its penis and right popliteal lymph node. The dog had severe blepharospasm, congestion of episcleral vessels and rubeosis iridis of the left eye. A presumptive diagnosis of transmissible venereal tumour (TVT) and iridocyclitis was made based on the results of fine needle aspiration. Chemotherapy with vincristine and prednisolone was initiated and after four months the dog made a complete recovery. However, the dog subsequently relapsed, showing miosis, blepharospasm and a well defined mass within the anterior chamber of the left eye. In addition, the dog exhibited generalised 'grand mal' type seizures. Computed tomographic (CT) examination of the brain revealed two distinct masses in the left frontal lobe. Because of the poor prognosis, the owners elected to have the dog euthanased. On histopathology, metastases of TVT in the left eye and left cerebral hemisphere were found, showing no specific staining for CD3, immunoglobulin (Ig) G, IgM and lambda light chains. It was therefore concluded that the tumour growth was progressive, and that there was an absence of local humoral immune response against TVT in this case. PMID:10812546

Ferreira, A J; Jaggy, A; Varejão, A P; Ferreira, M L; Correia, J M; Mulas, J M; Almeida, O; Oliveira, P; Prada, J

2000-04-01

78

Quality and readability of information materials for people with brain tumours and their families.  

PubMed

Written information is commonly used to inform patients about their disease and treatment but must be evidence-based and understandable to be useful. This study assessed the quality of the content and the readability of information brochures for people affected by brain tumours. We randomly selected 18 publicly available brochures. Brochures were assessed by criteria to assess the quality of content using the DISCERN instrument. Readability was tested using three commonly used formulas, which yield the reading grade level required to comprehend the brochure (sixth grade level recommended). The mean overall DISCERN score was 3.17 out of a maximum of 5 (moderate quality); only one achieved a rating greater than 4 (high quality). Only one brochure met the sixth grade readability criteria. Although brochures may have accurate content, few satisfied all of the recommended criteria to evaluate their content. Existing brochures need to be critically reviewed and simplified and consumer-focused brochures, produced. PMID:22918795

Langbecker, Danette; Janda, Monika

2012-12-01

79

An improved monomeric infrared fluorescent protein for neuronal and tumour brain imaging.  

PubMed

Infrared fluorescent proteins (IFPs) are ideal for in vivo imaging, and monomeric versions of these proteins can be advantageous as protein tags or for sensor development. In contrast to GFP, which requires only molecular oxygen for chromophore maturation, phytochrome-derived IFPs incorporate biliverdin (BV) as the chromophore. However, BV varies in concentration in different cells and organisms. Here we engineered cells to express the haeme oxygenase responsible for BV biosynthesis and a brighter monomeric IFP mutant (IFP2.0). Together, these tools improve the imaging capabilities of IFP2.0 compared with monomeric IFP1.4 and dimeric iRFP. By targeting IFP2.0 to the plasma membrane, we demonstrate robust labelling of neuronal processes in Drosophila larvae. We also show that this strategy improves the sensitivity when imaging brain tumours in whole mice. Our work shows promise in the application of IFPs for protein labelling and in vivo imaging. PMID:24832154

Yu, Dan; Gustafson, William Clay; Han, Chun; Lafaye, Céline; Noirclerc-Savoye, Marjolaine; Ge, Woo-Ping; Thayer, Desiree A; Huang, Hai; Kornberg, Thomas B; Royant, Antoine; Jan, Lily Yeh; Jan, Yuh Nung; Weiss, William A; Shu, Xiaokun

2014-01-01

80

Primary malignant brain tumours, psychosocial distress and the intimate partner experience: what do we know?  

PubMed

From the time of diagnosis of a primary malignant brain tumour (PMBT) and throughout the illness trajectory, the patient and intimate partner face many psychosocial challenges ranging from fear and uncertainty to hope and loss (Fox & Lantz, 1998; Janda et al., 2007; Kvale, Murthy, Taylor, Lee, & Nabors, 2009). While many patients diagnosed with cancer may go on to live with cancer as a chronic illness, this may not be said of individuals diagnosed with a PMBT, in particular those diagnosed with a glioma, the most common form of brain tumour (Gupta & Sarin, 2002). Gliomas are associated with a short disease trajectory and multiple deficits (functional, cognitive and psychiatric). What makes the PMBT experience unique from other cancers is that the intimate partner must not only deal with the diagnosis of cancer in their spouse, but also the accompanying personality, functional and behavioural changes wrought by the disease, as well as grieve the loss of the person they once knew (Sherwood et al., 2004). These multi-dimensional deficits are thought to place the intimate partner, as caregiver, at greater risk for adverse psychosocial effects such as anxiety, depression and post traumatic stress (Goebel, von Harscher, & Mehdorn, 2011; Keir, Farland, Lipp, & Friedman, 2009). The following discussion will provide an overview of the extant literature on the experience of living with a PMBT from the intimate partner (spouse) perspective with a particular emphasis on how intimate partners cope. The intimate partner is considered to be the heterosexual or same-sex, married or common-law partner of the patient. Highlights from the psychotherapy practice of the author will be used to further strengthen the need for more research, education and enhanced practice to more effectively meet the unique needs of this under-researched and supported population. PMID:25638913

Sabo, Brenda

2014-01-01

81

Radioisotope scanning of brain, liver, lung and bone with a note on tumour localizing agents  

PubMed Central

Radioisotopic scanning of brain, liver, lungs and the skeleton is briefly reviewed with a survey of recent developments of clinical significance. In brain scanning neoplasm detection rates of greater than 90% are claimed. The true figure is probably 70-80%. Autopsy data shows a number of false negatives, particularly with vascular lesions. Attempts to make scanning more specific in differentiating neoplasm from vascular lesions by rapid sequence blood flow studies are reviewed. In liver scanning by means of colloids again high success rate is claimed but small metastases are frequently missed and the false negative scan rate is probably quite high. Lung scanning still has its main place in investigating pulmonary embolic disease. Ventilation studies using Xenon 133 are useful, particularly combined with perfusion studies. The various radiopharmaceuticals for use in bone scanning are reviewed. The appearance of technetium labelled phosphate compounds will probably allow much wider use of total skeletal scanning. Research into tumour localizing agents continues, the most recent and interesting being Gallium citrate and labelled bleomycin. Neither agent is predictable however although Gallium may have a place in Hodgkins disease and bronchogenic neoplasm and both may have a place in the detection of cerebral tumours. ImagesFig. 1Fig. 2Fig. 3p452-bFig. 3bFig. 4Fig. 5Fig. 5bFig. 6Fig. 7Fig. 8Fig. 9Fig. 10Fig. 11Fig. 12Fig. 12c & 12dFig. 13Fig. 13 b,c,dFig. 14Fig. 14bFig. 15Fig. 15bFig. 16Fig. 17Fig. 18 PMID:4602127

Lavender, J. P.

1973-01-01

82

Challenges in providing culturally-competent care to patients with metastatic brain tumours and their families.  

PubMed

Being diagnosed with a metastatic brain tumour can be devastating as it is characterized by very low cure rates, as well as significant morbidity and mortality. Given the poor life expectancy and progressive disability that ensues, patients and family members experience much turmoil, which includes losses that bring about changes to family roles, routines and relationships. Crisis and conflict are common during such major disruptions to a family system, as individual members attempt to make sense of the illness experience based on cultural and spiritual beliefs, past experiences and personal philosophies. It is imperative health care providers strive towards increased awareness and knowledge of how culture affects the overall experience of illness and death in order to help create a mutually satisfactory care plan. Providing culturally-competent care entails the use of proper communication skills to facilitate the exploration of patient and family perspectives and allows for mutual decision making. A case study will illustrate the challenges encountered in providing culturally-competent care to a woman with brain cancer and her family. As the patient's health declined, the family entered into a state of crisis where communication between family members and health care professionals was strained; leading to conflict and sub-optimal outcomes. This paper will address the ethical dilemma of providing culturally-competent care when a patient's safety is at risk, and the nursing implications of upholding best practices in the context of differing beliefs and priorities. PMID:25265763

Longo, Lianne; Slater, Serena

2014-01-01

83

TENSOR CLASSIFICATION FOR P300-BASED BRAIN COMPUTER INTERFACE Akinari Onishi  

E-print Network

, tensor, higher order discriminant analysis (HODA), electroencephalography (EEG), event-related potentials of brain signals [1]. Feature extraction and classification of electroencephalography (EEG) signals

Cichocki, Andrzej

84

Multiclass brain-computer interface classification by Riemannian geometry.  

PubMed

This paper presents a new classification framework for brain-computer interface (BCI) based on motor imagery. This framework involves the concept of Riemannian geometry in the manifold of covariance matrices. The main idea is to use spatial covariance matrices as EEG signal descriptors and to rely on Riemannian geometry to directly classify these matrices using the topology of the manifold of symmetric and positive definite (SPD) matrices. This framework allows to extract the spatial information contained in EEG signals without using spatial filtering. Two methods are proposed and compared with a reference method [multiclass Common Spatial Pattern (CSP) and Linear Discriminant Analysis (LDA)] on the multiclass dataset IIa from the BCI Competition IV. The first method, named minimum distance to Riemannian mean (MDRM), is an implementation of the minimum distance to mean (MDM) classification algorithm using Riemannian distance and Riemannian mean. This simple method shows comparable results with the reference method. The second method, named tangent space LDA (TSLDA), maps the covariance matrices onto the Riemannian tangent space where matrices can be vectorized and treated as Euclidean objects. Then, a variable selection procedure is applied in order to decrease dimensionality and a classification by LDA is performed. This latter method outperforms the reference method increasing the mean classification accuracy from 65.1% to 70.2%. PMID:22010143

Barachant, Alexandre; Bonnet, Stéphane; Congedo, Marco; Jutten, Christian

2012-04-01

85

Risk of brain tumours in relation to estimated RF dose from mobile phones: results from five Interphone countries  

PubMed Central

Objectives The objective of this study was to examine the associations of brain tumours with radio frequency (RF) fields from mobile phones. Methods Patients with brain tumour from the Australian, Canadian, French, Israeli and New Zealand components of the Interphone Study, whose tumours were localised by neuroradiologists, were analysed. Controls were matched on age, sex and region and allocated the ‘tumour location’ of their matched case. Analyses included 553 glioma and 676 meningioma cases and 1762 and 1911 controls, respectively. RF dose was estimated as total cumulative specific energy (TCSE; J/kg) absorbed at the tumour's estimated centre taking into account multiple RF exposure determinants. Results ORs with ever having been a regular mobile phone user were 0.93 (95% CI 0.73 to 1.18) for glioma and 0.80 (95% CI 0.66 to 0.96) for meningioma. ORs for glioma were below 1 in the first four quintiles of TCSE but above 1 in the highest quintile, 1.35 (95% CI 0.96 to 1.90). The OR increased with increasing TCSE 7+ years before diagnosis (p-trend 0.01; OR 1.91, 95% CI 1.05 to 3.47 in the highest quintile). A complementary analysis in which 44 glioma and 135 meningioma cases in the most exposed area of the brain were compared with gliomas and meningiomas located elsewhere in the brain showed increased ORs for tumours in the most exposed part of the brain in those with 10+ years of mobile phone use (OR 2.80, 95% CI 1.13 to 6.94 for glioma). Patterns for meningioma were similar, but ORs were lower, many below 1.0. Conclusions There were suggestions of an increased risk of glioma in long-term mobile phone users with high RF exposure and of similar, but apparently much smaller, increases in meningioma risk. The uncertainty of these results requires that they be replicated before a causal interpretation can be made. PMID:21659469

Armstrong, B K; Bowman, J D; Giles, G G; Hours, M; Krewski, D; McBride, M; Parent, M E; Sadetzki, S; Woodward, A; Brown, J; Chetrit, A; Figuerola, J; Hoffmann, C; Jarus-Hakak, A; Montestruq, L; Nadon, L; Richardson, L; Villegas, R; Vrijheid, M

2011-01-01

86

Identification and Classification of Hubs in Brain Networks  

PubMed Central

Brain regions in the mammalian cerebral cortex are linked by a complex network of fiber bundles. These inter-regional networks have previously been analyzed in terms of their node degree, structural motif, path length and clustering coefficient distributions. In this paper we focus on the identification and classification of hub regions, which are thought to play pivotal roles in the coordination of information flow. We identify hubs and characterize their network contributions by examining motif fingerprints and centrality indices for all regions within the cerebral cortices of both the cat and the macaque. Motif fingerprints capture the statistics of local connection patterns, while measures of centrality identify regions that lie on many of the shortest paths between parts of the network. Within both cat and macaque networks, we find that a combination of degree, motif participation, betweenness centrality and closeness centrality allows for reliable identification of hub regions, many of which have previously been functionally classified as polysensory or multimodal. We then classify hubs as either provincial (intra-cluster) hubs or connector (inter-cluster) hubs, and proceed to show that lesioning hubs of each type from the network produces opposite effects on the small-world index. Our study presents an approach to the identification and classification of putative hub regions in brain networks on the basis of multiple network attributes and charts potential links between the structural embedding of such regions and their functional roles. PMID:17940613

Sporns, Olaf; Honey, Christopher J.; Kötter, Rolf

2007-01-01

87

LINT, a novel dL(3)mbt-containing complex, represses malignant brain tumour signature genes.  

PubMed

Mutations in the l(3)mbt tumour suppressor result in overproliferation of Drosophila larval brains. Recently, the derepression of different gene classes in l(3)mbt mutants was shown to be causal for transformation. However, the molecular mechanisms of dL(3)mbt-mediated gene repression are not understood. Here, we identify LINT, the major dL(3)mbt complex of Drosophila. LINT has three core subunits-dL(3)mbt, dCoREST, and dLint-1-and is expressed in cell lines, embryos, and larval brain. Using genome-wide ChIP-Seq analysis, we show that dLint-1 binds close to the TSS of tumour-relevant target genes. Depletion of the LINT core subunits results in derepression of these genes. By contrast, histone deacetylase, histone methylase, and histone demethylase activities are not required to maintain repression. Our results support a direct role of LINT in the repression of brain tumour-relevant target genes by restricting promoter access. PMID:22570633

Meier, Karin; Mathieu, Eve-Lyne; Finkernagel, Florian; Reuter, L Maximilian; Scharfe, Maren; Doehlemann, Gunther; Jarek, Michael; Brehm, Alexander

2012-01-01

88

Respiratory Deleted in Malignant Brain Tumours 1 (DMBT1) levels increase during lung maturation and infection  

PubMed Central

Deleted in Malignant Brain Tumours 1 (DMBT1) is a secreted scavenger receptor cysteine-rich protein that binds and aggregates various bacteria and viruses in vitro. Studies in adults have shown that DMBT1 is expressed mainly by mucosal epithelia and glands, in particular within the respiratory tract, and plays a role in innate immune defence. We hypothesized that respiratory DMBT1 levels may be influenced by various developmental and clinical factors such as maturity, age and bacterial infection. DMBT1 levels were studied in 205 tracheal aspirate samples of 82 ventilated preterm and full-term infants by enzyme-linked immunosorbent assay. Possible effects of various clinical parameters were tested by multiple regression analysis. DMBT1 levels increased significantly with lung maturity (P < 0·0001 for both gestational and postnatal age) and in small-for-gestational-age infants (P = 0·0179). An increase of respiratory DMBT1 levels was detected in neonatal infections (P < 0·0001). These results were supported by Western blotting. Immunohistochemical analyses of archived newborn lung sections (n = 17) demonstrated high concentrations of DMBT1 in lungs of neonates with bacterial infections. Our data show that preterm infants are able to up-regulate DMBT1 in infection as an unspecific immune reaction. PMID:17991292

Müller, H; End, C; Weiss, C; Renner, M; Bhandiwad, A; Helmke, B M; Gassler, N; Hafner, M; Poustka, A; Mollenhauer, J; Poeschl, J

2008-01-01

89

A Generic Machine-Learning Tool for Online Whole Brain Classification from fMRI  

E-print Network

A Generic Machine-Learning Tool for Online Whole Brain Classification from fMRI Ori Cohen1 generic machine learning (ML) tool for real- time fMRI whole brain classification, which can be used or a robot. 1 Introduction Real time fMRI is a promising risk-free non-invasive method for several reasons

Koppel, Moshe

90

Homozygous PMS2 germline mutations in two families with early-onset haematological malignancy, brain tumours, HNPCC-associated tumours, and signs of neurofibromatosis type 1.  

PubMed

Heterozygous germline mutations in mismatch repair (MMR) genes MLH1, PMS2, MSH2, and MSH6 cause Lynch syndrome. New studies have indicated that biallelic mutations lead to a distinctive syndrome, childhood cancer syndrome (CCS), with haematological malignancies and tumours of brain and bowel early in childhood, often associated with signs of neurofibromatosis type 1. We provide further evidence for CCS reporting on six children from two consanguineous families carrying homozygous PMS2 germline mutations. In family 1, all four children had the homozygous p.I590Xfs mutation. Two had a glioblastoma at the age of 6 years and one of them had three additional Lynch-syndrome associated tumours at 15. Another sibling suffered from a glioblastoma at age 9, and the fourth sibling had infantile myofibromatosis at 1. In family 2, two of four siblings were homozygous for the p.G271V mutation. One had two colorectal cancers diagnosed at ages 13 and 14, the other had a Non-Hodgkin's lymphoma and a colorectal cancer at ages 10 and 11, respectively. All children with malignancies had multiple café-au-lait spots. After reviewing published cases of biallelic MMR gene mutations, we provide a concise description of CCS, revealing similarities in age distribution with carriers of heterozygous MMR gene mutations. PMID:17851451

Krüger, Stefan; Kinzel, Miriam; Walldorf, Constanze; Gottschling, Sven; Bier, Andrea; Tinschert, Sigrid; von Stackelberg, Arend; Henn, Wolfram; Görgens, Heike; Boue, Stephanie; Kölble, Konrad; Büttner, Reinhard; Schackert, Hans K

2008-01-01

91

Automated Model-Based Tissue Classification of MR Images of the Brain  

Microsoft Academic Search

We describe a fully automated method for model- based tissue classification of magnetic resonance (MR) images of the brain. The method interleaves classification with estimation of the model parameters, improving the classification at each iteration. The algorithm is able to segment single- and multi- spectral MR images, corrects for MR signal inhomogeneities, and incorporates contextual information by means of Markov

Koen Van Leemput; Frederik Maes; Dirk Vandermeulen; Paul Suetens

1999-01-01

92

Essential problems in the interpretation of epidemiologic evidence for an association between mobile phone use and brain tumours  

NASA Astrophysics Data System (ADS)

Due to the close proximity of a mobile phone to the head when placing a call, concerns have been raised that exposure from microwaves during mobile phone use may exert adverse health effects and, in particular, may increase the risk of brain tumours. In response to these concerns epidemiological studies have been conducted, most applying the case-control design. While epidemiology can provide decisive evidence for an association between an exposure and a disease fundamental problems arise if exposure is short compared to the natural history of the disease. For brain tumours latencies of decades have been implicated making special considerations about potential effects of exposures necessary that commence during an already growing tumour. It is shown that measures of disease risk like odds ratios and relative risks can under such circumstances not be interpreted as indicators of a long term effect on incidences in the exposed population. Besides this problem, the issues of a suitable exposure metric and the selection of endpoints are unresolved. It is shown that the solution of these problems affords knowledge about the mechanism of action by which exposure increases the risk of manifest disease.

Kundi, Michael

2010-11-01

93

FAST TRAUMATIC BRAIN INJURY CT SLICE INDEXING VIA ANATOMICAL FEATURE CLASSIFICATION  

E-print Network

FAST TRAUMATIC BRAIN INJURY CT SLICE INDEXING VIA ANATOMICAL FEATURE CLASSIFICATION Ruizhe Liu for Infocomm Research ABSTRACT Computed tomography (CT) is used widely in traumatic brain injury diagnosis. One diagnosis components. Specifically, computed tomography (CT) is used widely in traumatic brain injury (TBI

Tan, Chew Lim

94

Synergy between CD8 T Cells and Th1 or Th2 Polarised CD4 T Cells for Adoptive Immunotherapy of Brain Tumours  

PubMed Central

The feasibility of cancer immunotherapy mediated by T lymphocytes is now a clinical reality. Indeed, many tumour associated antigens have been identified for cytotoxic CD8 T cells, which are believed to be key mediators of tumour rejection. However, for aggressive malignancies in specialised anatomic sites such as the brain, a limiting factor is suboptimal tumour infiltration by CD8 T cells. Here we take advantage of recent advances in T cell biology to differentially polarise CD4 T cells in order to explore their capacity to enhance immunotherapy. We used an adoptive cell therapy approach to work with clonal T cell populations of defined specificity. Th1 CD4 T cells preferentially homed to and accumulated within intracranial tumours compared with Th2 CD4 T cells. Moreover, tumour-antigen specific Th1 CD4 T cells enhanced CD8 T cell recruitment and function within the brain tumour bed. Survival of mice bearing intracranial tumours was significantly prolonged when CD4 and CD8 T cells were co-transferred. These results should encourage further definition of tumour antigens recognised by CD4 T cells, and exploitation of both CD4 and CD8 T cell subsets to optimise T cell therapy of cancer. PMID:23717511

Hoepner, Sabine; Loh, Jacelyn M. S.; Riccadonna, Cristina; Derouazi, Madiha; Maroun, Céline Yacoub; Dietrich, Pierre-Yves; Walker, Paul R.

2013-01-01

95

Lost in laterality: interpreting ''preferred side of the head during mobile phone use and risk of brain tumour'' associations.  

PubMed

Due to the highly localized exposure from mobile phones, the preferred side of the head during their use is important information when investigating a possible link with brain tumour risk, but at the same time, error and bias hamper the assessment of this information in case-control studies. Current studies provide evidence of reporting bias insofar as cases appear to over-report the side of the head where the tumour occurred as the one that they preferred in the past when using mobile phones. More refined methods of analysis among only cases or prospective studies with an assessment of the laterality of mobile phone use before the diagnosis of disease are needed to evaluate whether associations seen in some studies are entirely due to reporting bias or a mixture of reporting bias and a causal effect. PMID:19581357

Schüz, Joachim

2009-08-01

96

Brain connectivity and novel network measures for Alzheimer's disease classification.  

PubMed

We compare a variety of different anatomic connectivity measures, including several novel ones, that may help in distinguishing Alzheimer's disease (AD) patients from controls. We studied diffusion-weighted magnetic resonance imaging from 200 subjects scanned as part of the Alzheimer's Disease Neuroimaging Initiative. We first evaluated measures derived from connectivity matrices based on whole-brain tractography; next, we studied additional network measures based on a novel flow-based measure of brain connectivity, computed on a dense 3-dimensional lattice. Based on these 2 kinds of connectivity matrices, we computed a variety of network measures. We evaluated the measures' ability to discriminate disease with a repeated, stratified 10-fold cross-validated classifier, using support vector machines, a supervised learning algorithm. We tested the relative importance of different combinations of features based on the accuracy, sensitivity, specificity, and feature ranking of the classification of 200 people into normal healthy controls and people with early or late mild cognitive impairment or AD. PMID:25264345

Prasad, Gautam; Joshi, Shantanu H; Nir, Talia M; Toga, Arthur W; Thompson, Paul M

2015-01-01

97

Kinetic analysis of novel mono- and multivalent VHH-fragments and their application for molecular imaging of brain tumours  

PubMed Central

Background and purpose: The overexpression of epidermal growth factor receptor (EGFR) and its mutated variant EGFRvIII occurs in 50% of glioblastoma multiforme. We developed antibody fragments against EGFR/EGFRvIII for molecular imaging and/or therapeutic targeting applications. Experimental approach: An anti–EGFR/EGFRvIII llama single-domain antibody (EG2) and two higher valency format constructs, bivalent EG2-hFc and pentavalent V2C-EG2 sdAbs, were analysed in vitro for their binding affinities using surface plasmon resonance and cell binding studies, and in vivo using pharmacokinetic, biodistribution, optical imaging and fluorescent microscopy studies. Key results: Kinetic binding analyses by surface plasmon resonance revealed intrinsic affinities of 55 nM and 97 nM for the monovalent EG2 to immobilized extracellular domains of EGFR and EGFRvIII, respectively, and a 10- to 600-fold increases in apparent affinities for the multivalent binders, V2C-EG2 and EG2-hFc, respectively. In vivo pharmacokinetic and biodistribution studies in mice revealed plasma half-lives for EG2, V2C-EG2 and EG2-hFc of 41 min, 80 min and 12.5 h, respectively, as well as a significantly higher retention of EG2-hFc compared to the other two constructs in EGFR/EGFRvIII-expressing orthotopic brain tumours, resulting in the highest signal in the tumour region in optical imaging studies. Time domain volumetric optical imaging fusion with high-resolution micro-computed tomography of microvascular brain network confirmed EG2-hFc selective accumulation/retention in anatomically defined tumour regions. Conclusions: Single domain antibodies can be optimized for molecular imaging applications by methods that improve their apparent affinity and prolong plasma half-life and, at the same time, preserve their ability to penetrate tumour parenchyma. PMID:20590596

Iqbal, U; Trojahn, U; Albaghdadi, H; Zhang, J; O'Connor-McCourt, M; Stanimirovic, D; Tomanek, B; Sutherland, G; Abulrob, A

2010-01-01

98

Correlation of nodal mast cells with clinical outcome in dogs with mast cell tumour and a proposed classification system for the evaluation of node metastasis.  

PubMed

Lymph node metastasis in dogs with mast cell tumour has been reported as a negative prognostic indicator; however, no standardized histological criteria exist to define metastatic disease. The primary aim of this study was to determine whether different histological patterns of node-associated mast cells correlate with clinical outcome in dogs with mast cell tumour. A secondary goal was to propose a criteria-defined classification system for histological evaluation of lymph node metastasis. The Colorado State University Diagnostic Medicine Center database was searched for cases of canine mast cell tumours with reported lymph node metastasis or evidence of node-associated mast cells. Additional cases were obtained from a clinical trial involving sentinel lymph node mapping and node extirpation in dogs with mast cell neoplasia. Forty-one cases were identified for inclusion in the study. Demographic data, treatment and clinical outcome were collected for each case. Lymph nodes were classified according to a novel classification system (HN0-HN3) based on the number of, distribution of, and architectural disruption by, nodal mast cells. The findings of this study indicate that characterization of nodal mast cells as proposed by this novel classification system correlates with, and is prognostic for, clinical outcome in dogs with mast cell tumours. PMID:25172053

Weishaar, K M; Thamm, D H; Worley, D R; Kamstock, D A

2014-11-01

99

The frequency and cause of anxiety and depression amongst patients with malignant brain tumours between surgery and radiotherapy  

Microsoft Academic Search

Introduction  Between surgery and radiotherapy patients with a malignant glioma may encounter a number of psychosocial issues that could\\u000a invoke an anxious or depressive response. This study explored the frequency, severity and cause of anxiety and depression\\u000a in patients with presumed malignant brain tumours in the period between their surgery and radiotherapy.\\u000a \\u000a \\u000a \\u000a Methods  A prospective study of 51 patients used mixed methods

Lynn Kilbride; Graeme Smith; Robin Grant

2007-01-01

100

Known glioma risk loci are associated with glioma with a family history of brain tumours -- a case-control gene association study.  

PubMed

Familial cancer can be used to leverage genetic association studies. Recent genome-wide association studies have reported independent associations between seven single nucleotide polymorphisms (SNPs) and risk of glioma. The aim of this study was to investigate whether glioma cases with a positive family history of brain tumours, defined as having at least one first- or second-degree relative with a history of brain tumour, are associated with known glioma risk loci. One thousand four hundred and thirty-one glioma cases and 2,868 cancer-free controls were identified from four case-control studies and two prospective cohorts from USA, Sweden and Denmark and genotyped for seven SNPs previously reported to be associated with glioma risk in case-control designed studies. Odds ratios were calculated by unconditional logistic regression. In analyses including glioma cases with a family history of brain tumours (n = 104) and control subjects free of glioma at baseline, three of seven SNPs were associated with glioma risk: rs2736100 (5p15.33, TERT), rs4977756 (9p21.3, CDKN2A-CDKN2B) and rs6010620 (20q13.33, RTEL1). After Bonferroni correction for multiple comparisons, only one marker was statistically significantly associated with glioma risk, rs6010620 (ORtrend for the minor (A) allele, 0.39; 95% CI: 0.25-0.61; Bonferroni adjusted ptrend , 1.7 × 10(-4) ). In conclusion, as previously shown for glioma regardless of family history of brain tumours, rs6010620 (RTEL1) was associated with an increased risk of glioma when restricting to cases with family history of brain tumours. These findings require confirmation in further studies with a larger number of glioma cases with a family history of brain tumours. PMID:23115063

Melin, Beatrice; Dahlin, Anna M; Andersson, Ulrika; Wang, Zhaoming; Henriksson, Roger; Hallmans, Göran; Bondy, Melissa L; Johansen, Christoffer; Feychting, Maria; Ahlbom, Anders; Kitahara, Cari M; Wang, Sophia S; Ruder, Avima M; Carreón, Tania; Butler, Mary Ann; Inskip, Peter D; Purdue, Mark; Hsing, Ann W; Mechanic, Leah; Gillanders, Elizabeth; Yeager, Meredith; Linet, Martha; Chanock, Stephen J; Hartge, Patricia; Rajaraman, Preetha

2013-05-15

101

Known glioma risk loci are associated with glioma with a family history of brain tumours - a case-control gene association study  

PubMed Central

Familial cancer can be used to leverage genetic association studies. Recent genome-wide association studies have reported independent associations between seven single nucleotide polymorphisms (SNPs) and risk of glioma. The aim of this study was to investigate whether glioma cases with a positive family history of brain tumours, defined as having at least one first or second degree relative with a history of brain tumour, are associated with known glioma risk loci. 1431 glioma cases and 2868 cancer-free controls were identified from four case-control studies and two prospective cohorts from USA, Sweden, and Denmark and genotyped for seven SNPs previously reported to be associated with glioma risk in case-control designed studies. Odds ratios were calculated by unconditional logistic regression. In analyses including glioma cases with a family history of brain tumours (n=104) and control subjects free of glioma at baseline, three out of seven SNPs were associated with glioma risk; rs2736100 (5p15.33, TERT), rs4977756 (9p21.3, CDKN2A-CDKN2B), and rs6010620 (20q13.33, RTEL1). After Bonferroni correction for multiple comparisons, only one marker was statistically significantly associated with glioma risk, rs6010620 (ORtrend for the minor (A) allele, 0.39; 95% CI, 0.25–0.61; Bonferroni adjusted ptrend, 1.7×10?4). In conclusion, as previously shown for glioma regardless of family history of brain tumours, rs6010620 (RTEL1) was associated with an increased risk of glioma when restricting to cases with family history of brain tumours. These findings require confirmation in further studies with a larger number of glioma cases with a family history of brain tumours. PMID:23115063

Melin, Beatrice; Dahlin, Anna M.; Andersson, Ulrika; Wang, Zhaoming; Henriksson, Roger; Hallmans, Göran; Bondy, Melissa L.; Johansen, Christoffer; Feychting, Maria; Ahlbom, Anders; Kitahara, Cari M.; Wang, Sophia S.; Ruder, Avima M.; Carreón, Tania; Butler, Mary Ann; Inskip, Peter D.; Purdue, Mark; Hsing, Ann W.; Mechanic, Leah; Gillanders, Elizabeth; Yeager, Meredith; Linet, Martha; Chanock, Stephen J.; Hartge, Patricia; Rajaraman, Preetha

2012-01-01

102

Mir-34a Mimics Are Potential Therapeutic Agents for p53-Mutated and Chemo-Resistant Brain Tumour Cells  

PubMed Central

Chemotherapeutic drug resistance and relapse remains a major challenge for paediatric (medulloblastoma) and adult (glioblastoma) brain tumour treatment. Medulloblastoma tumours and cell lines with mutations in the p53 signalling pathway have been shown to be specifically insensitive to DNA damaging agents. The aim of this study was to investigate the potential of triggering cell death in p53 mutated medulloblastoma cells by a direct activation of pro-death signalling downstream of p53 activation. Since non-coding microRNAs (miRNAs) have the ability to fine tune the expression of a variety of target genes, orchestrating multiple downstream effects, we hypothesised that triggering the expression of a p53 target miRNA could induce cell death in chemo-resistant cells. Treatment with etoposide, increased miR-34a levels in a p53-dependent fashion and the level of miR-34a transcription was correlated with the cell sensitivity to etoposide. miR-34a activity was validated by measuring the expression levels of one of its well described target: the NADH dependent sirtuin1 (SIRT1). Whilst drugs directly targeting SIRT1, were potent to trigger cell death at high concentrations only, introduction of synthetic miR-34a mimics was able to induce cell death in p53 mutated medulloblastoma and glioblastoma cell lines. Our results show that the need of a functional p53 signaling pathway can be bypassed by direct activation of miR-34a in brain tumour cells. PMID:25250818

Fan, Yuen Ngan; Meley, Daniel; Pizer, Barry; Sée, Violaine

2014-01-01

103

MRI-image based radiotherapy treatment optimization of brain tumours using stochastic approach  

E-print Network

. Keywords: Tumour, Radiotherapy, Apoptosis, MRI, cell cycle. 1) Introduction Cancer [1] is known from the cell cycles as well as from the molecular properties of malignancy, the therapy of cancer cells, the effect of cytotoxic cells, the limited supply of nutrients and the mechanical pressure

Mishra, Prabhat

104

Agent-Based Distributed Decision Support System for Brain Tumour Diagnosis and Prognosis  

E-print Network

Universiteit Leuven, Departement Elektrotechniek, Belgium f University of Southampton, School of Electronics and Computer Science, UK g Birmingham Children's Hospital, UK h ITACA, Grupo BET- Informática Médica, UK-similar tumours can vary widely, particularly in children. Magnetic Resonance Spectroscopy (MRS) is a non

105

Real-time classification of activated brain areas for fMRI-based human-brain-interfaces  

NASA Astrophysics Data System (ADS)

Functional MR imaging (fMRI) enables to detect different activated brain areas according to the performed tasks. However, data are usually evaluated after the experiment, which prohibits intra-experiment optimization or more sophisticated applications such as biofeedback experiments. Using a human-brain-interface (HBI), subjects are able to communicate with external programs, e.g. to navigate through virtual scenes, or to experience and modify their own brain activation. These applications require the real-time analysis and classification of activated brain areas. Our paper presents first results of different strategies for real-time pattern analysis and classification realized within a flexible experiment control system that enables the volunteers to move through a 3D virtual scene in real-time using finger tapping tasks, and alternatively only thought-based tasks.

Moench, Tobias; Hollmann, Maurice; Grzeschik, Ramona; Mueller, Charles; Luetzkendorf, Ralf; Baecke, Sebastian; Luchtmann, Michael; Wagegg, Daniela; Bernarding, Johannes

2008-03-01

106

An improved brain image classification technique with mining and shape prior segmentation procedure.  

PubMed

The shape prior segmentation procedure and pruned association rule with ImageApriori algorithm has been used to develop an improved brain image classification system are presented in this paper. The CT scan brain images have been classified into three categories namely normal, benign and malignant, considering the low-level features extracted from the images and high level knowledge from specialists to enhance the accuracy in decision process. The experimental results on pre-diagnosed brain images showed 97% sensitivity, 91% specificity and 98.5% accuracy. The proposed algorithm is expected to assist the physicians for efficient classification with multiple key features per image. PMID:20703655

Rajendran, P; Madheswaran, M

2012-04-01

107

Development of a decision support system for diagnosis and grading of brain tumours using in vivo magnetic resonance single voxel spectra.  

PubMed

A computer-based decision support system to assist radiologists in diagnosing and grading brain tumours has been developed by the multi-centre INTERPRET project. Spectra from a database of 1H single-voxel spectra of different types of brain tumours, acquired in vivo from 334 patients at four different centres, are clustered according to their pathology, using automated pattern recognition techniques and the results are presented as a two-dimensional scatterplot using an intuitive graphical user interface (GUI). Formal quality control procedures were performed to standardize the performance of the instruments and check each spectrum, and teams of expert neuroradiologists, neurosurgeons, neurologists and neuropathologists clinically validated each case. The prototype decision support system (DSS) successfully classified 89% of the cases in an independent test set of 91 cases of the most frequent tumour types (meningiomas, low-grade gliomas and high-grade malignant tumours--glioblastomas and metastases). It also helps to resolve diagnostic difficulty in borderline cases. When the prototype was tested by radiologists and other clinicians it was favourably received. Results of the preliminary clinical analysis of the added value of using the DSS for brain tumour diagnosis with MRS showed a small but significant improvement over MRI used alone. In the comparison of individual pathologies, PNETs were significantly better diagnosed with the DSS than with MRI alone. PMID:16763971

Tate, Anne R; Underwood, Joshua; Acosta, Dionisio M; Julià-Sapé, Margarida; Majós, Carles; Moreno-Torres, Angel; Howe, Franklyn A; van der Graaf, Marinette; Lefournier, Virginie; Murphy, Mary M; Loosemore, Alison; Ladroue, Christophe; Wesseling, Pieter; Luc Bosson, Jean; Cabañas, Miquel E; Simonetti, Arjan W; Gajewicz, Witold; Calvar, Jorge; Capdevila, Antoni; Wilkins, Peter R; Bell, B Anthony; Rémy, Chantal; Heerschap, Arend; Watson, Des; Griffiths, John R; Arús, Carles

2006-06-01

108

Brain tumours at 7T MRI compared to 3T—contrast effect after half and full standard contrast agent dose: initial results  

PubMed Central

Objectives To compare the contrast agent effect of a full dose and half the dose of gadobenate dimeglumine in brain tumours at 7 Tesla (7T) MR versus 3 Tesla (3T). Methods Ten patients with primary brain tumours or metastases were examined. Signal intensities were assessed in the lesion and normal brain. Tumour-to-brain contrast and lesion enhancement were calculated. Additionally, two independent readers subjectively graded the image quality and artefacts. Results The enhanced mean tumour-to-brain contrast and lesion enhancement were significantly higher at 7T than at 3T for both half the dose (91.8±45.8 vs. 43.9±25.3 [p=0.010], 128.1±53.7 vs. 75.5±32.4 [p=0.004]) and the full dose (129.2±50.9 vs. 66.6±33.1 [p=0.002], 165.4±54.2 vs. 102.6±45.4 [p=0.004]). Differences between dosages at each field strength were also significant. Lesion enhancement was higher with half the dose at 7T than with the full dose at 3T (p=.037), while the tumour-to-brain contrast was not significantly different. Subjectively, contrast enhancement, visibility, and lesion delineation were better at 7T and with the full dose. All parameters were rated as good, at the least. Conclusion Half the routine contrast agent dose at 7T provided higher lesion enhancement than the full dose at 3T which indicates the possibility of dose reduction at 7T. PMID:25194707

Noebauer-Huhmann, Iris-Melanie; Szomolanyi, P.; Kronnerwetter, C.; Widhalm, G.; Weber, M.; Nemec, S.; Juras, V.; Ladd, M. E.; Prayer, D.; Trattnig, S.

2015-01-01

109

Classification of whole brain fMRI activation patterns  

E-print Network

Functional magnetic resonance imaging (fMRI) is an imaging technology which is primarily used to perform brain activation studies by measuring neural activity in the brain. It is an interesting question whether patterns ...

Balc?, Serdar Kemal

2008-01-01

110

In-phantom two-dimensional thermal neutron distribution for intraoperative boron neutron capture therapy of brain tumours.  

PubMed

The aim of this study was to determine the in-phantom thermal neutron distribution derived from neutron beams for intraoperative boron neutron capture therapy (IOBNCT). Gold activation wires arranged in a cylindrical water phantom with (void-in-phantom) or without (standard phantom) a cylinder styrene form placed inside were irradiated by using the epithermal beam (ENB) and the mixed thermal-epithermal beam (TNB-1) at the Japan Research Reactor No 4. With ENB, we observed a flattened distribution of thermal neutron flux and a significantly enhanced thermal flux delivery at a depth compared with the results of using TNB-1. The thermal neutron distribution derived from both the ENB and TNB-1 was significantly improved in the void-in-phantom, and a double high dose area was formed lateral to the void. The flattened distribution in the circumference of the void was observed with the combination of ENB and the void-in-phantom. The measurement data suggest that the ENB may provide a clinical advantage in the form of an enhanced and flattened dose delivery to the marginal tissue of a post-operative cavity in which a residual and/or microscopically infiltrating tumour often occurs. The combination of the epithermal neutron beam and IOBNCT will improve the clinical results of BNCT for brain tumours. PMID:12171329

Yamamoto, T; Matsumura, A; Yamamoto, K; Kumada, H; Shibata, Y; Nose, T

2002-07-21

111

A parameter study to determine the optimal source neutron energy in boron neutron capture therapy of brain tumours.  

PubMed

The values of the parameters used in boron neutron capture therapy (BNCT) to calculate a given dose to human tissue vary with patients due to different physical, biological and/or medical circumstances. Parameters include the tissue dimensions, the 10B concentration and the relative biological effectiveness (RBE) factors for the different dose components associated with BNCT. Because there is still no worldwide agreement on RBE values, more often than not, average values for these parameters are used. It turns out that the RBE-problem can be circumvented by taking into account all imaginable parameter values. Approaching this quest from another angle: the outcome will also provide the parameters (and values) which influence the optimal source neutron energy. For brain tumours it turns out that the 10B concentration, the RBE factors for 10B as well as fast neutrons, together with the dose limit set for healthy tissue, affect the optimal BNCT source neutron energy. By using source neutrons of a few keV together with neutrons of a few eV, it ensures that, under all imaginable circumstances, a maximum of alpha (and lithium) particles can be delivered in the tumour. PMID:15509065

Nievaart, V A; Moss, R L; Kloosterman, J L; van der Hagen, T H J J; van Dam, H

2004-09-21

112

Imaging of adult astrocytic brain tumours with 7 T MRI: preliminary results  

Microsoft Academic Search

Purpose  In this study tumour vascularity and necrosis of intracranial astrocytomas were compared using 7 T and 1.5 T magnetic resonance\\u000a imaging (MRI).\\u000a \\u000a \\u000a \\u000a \\u000a Methods  Fifteen patients with histologically proven astrocytomas (WHO grades II–IV) were prospectively examined at 1.5 T (Magnetom\\u000a Espree or Sonata) and 7 T (Magnetom 7 T, Siemens, Erlangen, Germany) with T2*-w (weighted), T1-w with (only a subset of five\\u000a patients at 7 T)

Christoph Moenninghoff; Stefan Maderwald; Jens M. Theysohn; Oliver Kraff; Mark E. Ladd; Nicolai El Hindy; Johannes van de Nes; Michael Forsting; Isabel Wanke

2010-01-01

113

Tissue Classification of Noisy MR Brain Images Using Constrained GMM  

Microsoft Academic Search

We present an automated algorithm for tissue segmentation of noisy, low contrast magnetic resonance (MR) images of the brain. We use a mixture model composed of a large number of Gaussians, with each brain tissue represented by a large number of the Gaussian components in order to capture the complex tissue spatial layout. The intensity of a tissue is considered

Amit Ruf; Hayit Greenspan; Jacob Goldberger

2005-01-01

114

Challenges relating to solid tumour brain metastases in clinical trials, part 1: patient population, response, and progression. A report from the RANO group.  

PubMed

Therapeutic outcomes for patients with brain metastases need to improve. A critical review of trials specifically addressing brain metastases shows key issues that could prevent acceptance of results by regulatory agencies, including enrolment of heterogeneous groups of patients and varying definitions of clinical endpoints. Considerations specific to disease, modality, and treatment are not consistently addressed. Additionally, the schedule of CNS imaging and consequences of detection of new or progressive brain metastases in trials mainly exploring the extra-CNS activity of systemic drugs are highly variable. The Response Assessment in Neuro-Oncology (RANO) working group is an independent, international, collaborative effort to improve the design of trials in patients with brain tumours. In this two-part series, we review the state of clinical trials of brain metastases and suggest a consensus recommendation for the development of criteria for future clinical trials. PMID:23993384

Lin, Nancy U; Lee, Eudocia Q; Aoyama, Hidefumi; Barani, Igor J; Baumert, Brigitta G; Brown, Paul D; Camidge, D Ross; Chang, Susan M; Dancey, Janet; Gaspar, Laurie E; Harris, Gordon J; Hodi, F Stephen; Kalkanis, Steven N; Lamborn, Kathleen R; Linskey, Mark E; Macdonald, David R; Margolin, Kim; Mehta, Minesh P; Schiff, David; Soffietti, Riccardo; Suh, John H; van den Bent, Martin J; Vogelbaum, Michael A; Wefel, Jeffrey S; Wen, Patrick Y

2013-09-01

115

UK case control study of brain tumours in children, teenagers and young adults: a pilot study  

PubMed Central

Background Tumours of the central nervous system are the second most common group of childhood cancers in 0–14 year olds (24% of total cancers) and represent a major diagnostic group in 15–24 year olds. The pilot case–control study aimed to establish methodologies for a future comprehensive aetiological investigation among children and young adults. Methods Eligible cases were newly diagnosed with an intracranial tumour of neuroepithelial tissue aged 0–24 years. The pilot recruited patients through Leeds and Manchester Principal Treatment Centres. Controls were drawn from general practice lists. Controls were frequency matched by age and gender. Results We interviewed 49 cases and 78 controls comprising 85% of the target sample size. Response rates were 52% for cases and 32% for controls. Completion of the questionnaire was successful, with a very small proportion of missing data being reported (5-10%). The age distribution of cases and controls was similar with around three-quarters of interviewed subjects aged 0–14. Half of cases and almost two-thirds of controls reported using a mobile phone with the majority starting between 10–14 years of age. Prevalence of breastfeeding was lower in cases than controls (Odds Ratio 0.4; 95% CI 0.2-1.2), whilst cases were more likely to be delivered by caesarean section (OR 1.6; 95% CI 0.6-4.4). Cases were significantly more likely to have a birthweight >?3.5 kg compared to controls. Cases were also more likely to come from a family with 3 or more siblings than controls (OR 3.0; 95% CI 0.7-13.6). The majority of participants (>80%) were in favour of taking either blood or saliva to aid molecular epidemiological research. Conclusions Successful methods were established for identifying and recruiting a high proportion of case subjects, exploiting strong links with the clinical teams at the treatment centres. Control procedures proved more difficult to implement. However, working closely with national clinical and professional research networks will enable improved control identification and recruitment, with good prospects for collecting biological samples in the future. PMID:24398074

2014-01-01

116

Schizophrenia Classification Using Regions of Interest in Brain MRI D. S. Cheng1  

E-print Network

Schizophrenia Classification Using Regions of Interest in Brain MRI D. S. Cheng1 , M. Bicego1 , U by schizophrenia and other mental illnesses traditionally diagnosed by self-reports and behavioral observations encouraging agreements with previous medical studies in schizophrenia research. 1 Introduction Computational

Castellani, Umberto

117

Multiple stages classification of Alzheimers disease based on structural brain networks using  

E-print Network

Multiple stages classification of Alzheimers disease based on structural brain networks using for a progressing disease such as Alzheimers dis- ease is a key issue for the disease prevention and treatment networks in the progression of the Alzheimers disease. Here we developed a framework to utilize generalized

Wang, Yalin

118

Extracting regional brain patterns for classification of neurodegenerative diseases  

NASA Astrophysics Data System (ADS)

In structural Magnetic Resonance Imaging (MRI), neurodegenerative diseases generally present complex brain patterns that can be correlated with di erent clinical onsets of this pathologies. An objective method that aims to determine both global and local changes is not usually available in clinical practice, thus the interpretation of these images is strongly dependent on the radiologist's skills. In this paper, we propose a strategy which interprets the brain structure using a framework that highlights discriminant brain patterns for neurodegenerative diseases. This is accomplished by combining a probabilistic learning technique, which identi es and groups regions with similar visual features, with a visual saliency method that exposes relevant information within each region. The association of such patterns with a speci c disease is herein evaluated in a classi cation task, using a dataset including 80 Alzheimer's disease (AD) patients and 76 healthy subjects (NC). Preliminary results show that the proposed method reaches a maximum classi cation accuracy of 81.39%.

Pulido, Andrea; Rueda, Andrea; Romero, Eduardo

2013-11-01

119

Support feature machine for classification of abnormal brain activity  

Microsoft Academic Search

In this study, a novel multidimensional time series classiflca- tion technique, namely support feature machine (SFM), is proposed. SFM is inspired by the optimization model of sup- port vector machine and the nearest neighbor rule to incor- porate both spatial and temporal of the multi-dimensional time series data. This paper also describes an application of SFM for detecting abnormal brain

Wanpracha Art Chaovalitwongse; Ya-ju Fan; Rajesh C. Sachdeo

2007-01-01

120

Brain tumour classification using short echo time 1 H MRS. Objective comparison of classification techniques (LDA, LS-SVM).  

E-print Network

techniques (LDA, LS-SVM). A. Devos1 , L. Lukas1 , J. A. K. Suykens1 , L. Vanhamme1 , F. A. Howe2 , C. Majós3 Analysis (PCA) prior to Linear Discriminant Analysis (LDA), Least Squares Support Vector Machines (LS-SVM) with a linear kernel and LS-SVM with a Radial Basis Function (RBF). LS-SVM is a kernel-based technique

121

Preliminary structural MRI based brain classification of chronic pelvic pain: A MAPP network study.  

PubMed

Neuroimaging studies have shown that changes in brain morphology often accompany chronic pain conditions. However, brain biomarkers that are sensitive and specific to chronic pelvic pain (CPP) have not yet been adequately identified. Using data from the Trans-MAPP Research Network, we examined the changes in brain morphology associated with CPP. We used a multivariate pattern classification approach to detect these changes and to identify patterns that could be used to distinguish participants with CPP from age-matched healthy controls. In particular, we used a linear support vector machine (SVM) algorithm to differentiate gray matter images from the 2 groups. Regions of positive SVM weight included several regions within the primary somatosensory cortex, pre-supplementary motor area, hippocampus, and amygdala were identified as important drivers of the classification with 73% overall accuracy. Thus, we have identified a preliminary classifier based on brain structure that is able to predict the presence of CPP with a good degree of predictive power. Our regional findings suggest that in individuals with CPP, greater gray matter density may be found in the identified distributed brain regions, which are consistent with some previous investigations in visceral pain syndromes. Future studies are needed to improve upon our identified preliminary classifier with integration of additional variables and to assess whether the observed differences in brain structure are unique to CPP or generalizable to other chronic pain conditions. PMID:25242566

Bagarinao, Epifanio; Johnson, Kevin A; Martucci, Katherine T; Ichesco, Eric; Farmer, Melissa A; Labus, Jennifer; Ness, Timothy J; Harris, Richard; Deutsch, Georg; Apkarian, A Vania; Mayer, Emeran A; Clauw, Daniel J; Mackey, Sean

2014-12-01

122

From genotypes to phenotypes: classification of the tumour profiles for different variants of the cadherin adhesion pathway  

NASA Astrophysics Data System (ADS)

The E-cadherin adhesive profile expressed by a tumour is a characterization of the intracellular and intercellular protein interactions that control cell-cell adhesion. Within the intracellular proteins that determine the tumour adhesive profile, Src and PI3 are two essentials to initiate the formation of the E-cadherin adhesion complex. On the other hand, Src has also the capability of disrupting the ?-catenin-E-cadherin complex and down-regulating cell-cell adhesion. In this paper, using a multi-scale mathematical model, we study the role of each of these proteins in the adhesive profile and invasive properties of the tumour. To do this, we create three versions of an intracellular model that explains the interplay between the proteins E-cadherin, ?-catenin, Src and PI3; and we couple them to the strength of the cell-cell adhesion forces within an individual-cell-based model. The simulation results show how the tumour profile and its aggressive potential may change depending on the intrinsic characteristics of the protein pathways, and how these pathways may influence the early stages of cancer invasion. Our major findings may be summarized as follows. (1) Intermediate levels of Src synthesis rates generate the least invasive tumour phenotype. (2) Conclusions drawn from findings obtained from the intracellular molecular dynamics (here cadherin-catenin binding complexes) to the multi-cellular invasive potential of a tumour may be misleading or erroneous. The conclusions should be validated in a multi-cellular context on timescales relevant for population growth. (3) Monoclonal populations of more cohesive cells with otherwise equal properties tend to grow slower. (4) Less cohesive cells tend to outcompete more cohesive cells. (5) Less cohesive cells have a larger probability of invasion as migration forces can more easily outbalance cohesive forces.

Ramis-Conde, Ignacio; Drasdo, Dirk

2012-06-01

123

Acute respiratory distress syndrome as a manifestation of brain stem tumour--a case report.  

PubMed

Acute lung injury (ALI), including acute respiratory distress syndrome (ARDS), is a critical condition consisting of acute hypoxaemic respiratory failure with bilateral pulmonary infiltrates of non-cardiogenic origin. Occasionally it develops in patients with acute or subacute central nervous system pathologies, such as increased intracranial pressure and brain stem lesions. The exact epidemiology of neurogenic pulmonary oedema is unknown. However, due to non-specific clinical manifestation it often remains undiagnosed. Its pathogenesis probably involves overactivation of the sympathetic autonomic system with pulmonary hypertension and increased vessel permeability. We present a case of successfully managed ARDS in a previously healthy patient with newly diagnosed and symptomatic haemangioblastoma of the medulla oblongata. In this context we also review current knowledge on the aetiopathogenesis, diagnostic criteria and treatment for neurogenic ARDS. PMID:20054760

Bilik, Marta; Karli?ski, Micha?; Cz?onkowska, Anna

2009-01-01

124

Classification of autism spectrum disorder using supervised learning of brain connectivity measures extracted from synchrostates  

NASA Astrophysics Data System (ADS)

Objective. The paper investigates the presence of autism using the functional brain connectivity measures derived from electro-encephalogram (EEG) of children during face perception tasks. Approach. Phase synchronized patterns from 128-channel EEG signals are obtained for typical children and children with autism spectrum disorder (ASD). The phase synchronized states or synchrostates temporally switch amongst themselves as an underlying process for the completion of a particular cognitive task. We used 12 subjects in each group (ASD and typical) for analyzing their EEG while processing fearful, happy and neutral faces. The minimal and maximally occurring synchrostates for each subject are chosen for extraction of brain connectivity features, which are used for classification between these two groups of subjects. Among different supervised learning techniques, we here explored the discriminant analysis and support vector machine both with polynomial kernels for the classification task. Main results. The leave one out cross-validation of the classification algorithm gives 94.7% accuracy as the best performance with corresponding sensitivity and specificity values as 85.7% and 100% respectively. Significance. The proposed method gives high classification accuracies and outperforms other contemporary research results. The effectiveness of the proposed method for classification of autistic and typical children suggests the possibility of using it on a larger population to validate it for clinical practice.

Jamal, Wasifa; Das, Saptarshi; Oprescu, Ioana-Anastasia; Maharatna, Koushik; Apicella, Fabio; Sicca, Federico

2014-08-01

125

The INTERPRET Decision-Support System version 3.0 for evaluation of Magnetic Resonance Spectroscopy data from human brain tumours and other abnormal brain masses  

PubMed Central

Background Proton Magnetic Resonance (MR) Spectroscopy (MRS) is a widely available technique for those clinical centres equipped with MR scanners. Unlike the rest of MR-based techniques, MRS yields not images but spectra of metabolites in the tissues. In pathological situations, the MRS profile changes and this has been particularly described for brain tumours. However, radiologists are frequently not familiar to the interpretation of MRS data and for this reason, the usefulness of decision-support systems (DSS) in MRS data analysis has been explored. Results This work presents the INTERPRET DSS version 3.0, analysing the improvements made from its first release in 2002. Version 3.0 is aimed to be a program that 1st, can be easily used with any new case from any MR scanner manufacturer and 2nd, improves the initial analysis capabilities of the first version. The main improvements are an embedded database, user accounts, more diagnostic discrimination capabilities and the possibility to analyse data acquired under additional data acquisition conditions. Other improvements include a customisable graphical user interface (GUI). Most diagnostic problems included have been addressed through a pattern-recognition based approach, in which classifiers based on linear discriminant analysis (LDA) were trained and tested. Conclusions The INTERPRET DSS 3.0 allows radiologists, medical physicists, biochemists or, generally speaking, any person with a minimum knowledge of what an MR spectrum is, to enter their own SV raw data, acquired at 1.5 T, and to analyse them. The system is expected to help in the categorisation of MR Spectra from abnormal brain masses. PMID:21114820

2010-01-01

126

Investigating machine learning techniques for MRI-based classification of brain neoplasms  

PubMed Central

Purpose Diagnosis and characterization of brain neoplasms appears of utmost importance for therapeutic management. The emerging of imaging techniques, such as Magnetic Resonance (MR) imaging, gives insight into pathology, while the combination of several sequences from conventional and advanced protocols (such as perfusion imaging) increases the diagnostic information. To optimally combine the multiple sources and summarize the information into a distinctive set of variables however remains difficult. The purpose of this study is to investigate machine learning algorithms that automatically identify the relevant attributes and are optimal for brain tumor differentiation. Methods Different machine learning techniques are studied for brain tumor classification based on attributes extracted from conventional and perfusion MRI. The attributes, calculated from neoplastic, necrotic, and edematous regions of interest, include shape and intensity characteristics. Attributes subset selection is performed aiming to remove redundant attributes using two filtering methods and a wrapper approach, in combination with three different search algorithms (Best First, Greedy Stepwise and Scatter). The classification frameworks are implemented using the WEKA software. Results The highest average classification accuracy assessed by leave-one-out (LOO) cross-validation on 101 brain neoplasms was achieved using the wrapper evaluator in combination with the Best First search algorithm and the KNN classifier and reached 96.9% when discriminating metastases from gliomas and 94.5% when discriminating high-grade from low-grade neoplasms. Conclusions A computer-assisted classification framework is developed and used for differential diagnosis of brain neoplasms based on MRI. The framework can achieve higher accuracy than most reported studies using MRI. PMID:21516321

Kanas, Vasileios G.; Davatzikos, Christos

2015-01-01

127

Classification of Alzheimer's disease using regional saliency maps from brain MR volumes  

NASA Astrophysics Data System (ADS)

Accurate diagnosis of Alzheimer's disease (AD) from structural Magnetic Resonance (MR) images is difficult due to the complex alteration of patterns in brain anatomy that could indicate the presence or absence of the pathology. Currently, an effective approach that allows to interpret the disease in terms of global and local changes is not available in the clinical practice. In this paper, we propose an approach for classification of brain MR images, based on finding pathology-related patterns through the identification of regional structural changes. The approach combines a probabilistic Latent Semantic Analysis (pLSA) technique, which allows to identify image regions through latent topics inferred from the brain MR slices, with a bottom-up Graph-Based Visual Saliency (GBVS) model, which calculates maps of relevant information per region. Regional saliency maps are finally combined into a single map on each slice, obtaining a master saliency map of each brain volume. The proposed approach includes a one-to-one comparison of the saliency maps which feeds a Support Vector Machine (SVM) classifier, to group test subjects into normal or probable AD subjects. A set of 156 brain MR images from healthy (76) and pathological (80) subjects, splitted into a training set (10 non-demented and 10 demented subjects) and one testing set (136 subjects), was used to evaluate the performance of the proposed approach. Preliminary results show that the proposed method reaches a maximum classification accuracy of 87.21%.

Pulido, Andrea; Rueda, Andrea; Romero, Eduardo

2013-02-01

128

Non-target adjacent stimuli classification improves performance of classical ERP-based brain computer interface  

NASA Astrophysics Data System (ADS)

Objective. The classical ERP-based speller, or P300 Speller, is one of the most commonly used paradigms in the field of Brain Computer Interfaces (BCI). Several alterations to the visual stimuli presentation system have been developed to avoid unfavorable effects elicited by adjacent stimuli. However, there has been little, if any, regard to useful information contained in responses to adjacent stimuli about spatial location of target symbols. This paper aims to demonstrate that combining the classification of non-target adjacent stimuli with standard classification (target versus non-target) significantly improves classical ERP-based speller efficiency. Approach. Four SWLDA classifiers were trained and combined with the standard classifier: the lower row, upper row, right column and left column classifiers. This new feature extraction procedure and the classification method were carried out on three open databases: the UAM P300 database (Universidad Autonoma Metropolitana, Mexico), BCI competition II (dataset IIb) and BCI competition III (dataset II). Main results. The inclusion of the classification of non-target adjacent stimuli improves target classification in the classical row/column paradigm. A gain in mean single trial classification of 9.6% and an overall improvement of 25% in simulated spelling speed was achieved. Significance. We have provided further evidence that the ERPs produced by adjacent stimuli present discriminable features, which could provide additional information about the spatial location of intended symbols. This work promotes the searching of information on the peripheral stimulation responses to improve the performance of emerging visual ERP-based spellers.

Ceballos, G. A.; Hernández, L. F.

2015-04-01

129

Classification of Autism Spectrum Disorder Using Supervised Learning of Brain Connectivity Measures Extracted from Synchrostates  

E-print Network

Objective. The paper investigates the presence of autism using the functional brain connectivity measures derived from electro-encephalogram (EEG) of children during face perception tasks. Approach. Phase synchronized patterns from 128-channel EEG signals are obtained for typical children and children with autism spectrum disorder (ASD). The phase synchronized states or synchrostates temporally switch amongst themselves as an underlying process for the completion of a particular cognitive task. We used 12 subjects in each group (ASD and typical) for analyzing their EEG while processing fearful, happy and neutral faces. The minimal and maximally occurring synchrostates for each subject are chosen for extraction of brain connectivity features, which are used for classification between these two groups of subjects. Among different supervised learning techniques, we here explored the discriminant analysis and support vector machine both with polynomial kernels for the classification task. Main results. The leave ...

Jamal, Wasifa; Oprescu, Ioana-Anastasia; Maharatna, Koushik; Apicella, Fabio; Sicca, Federico

2014-01-01

130

Adaptive Markov modeling for mutual-information-based, unsupervised MRI brain-tissue classification  

Microsoft Academic Search

This paper presents a novel method for brain-tissue classification in magnetic reso- nance (MR) images that relies on a very general, adaptive statistical model of image neighborhoods. The method models MR-tissue intensities as derived from station- ary random fields. It models the associated Markov statistics nonparametrically via a data-driven strategy. This paper describes the essential theoretical aspects un- derpinning adaptive,

Suyash P. Awate; Tolga Tasdizen; Norman L. Foster; Ross T. Whitaker

2006-01-01

131

Functional connectivity classification of autism identifies highly predictive brain features but falls short of biomarker standards  

PubMed Central

Objectives Autism spectrum disorders (ASD) are diagnosed based on early-manifesting clinical symptoms, including markedly impaired social communication. We assessed the viability of resting-state functional MRI (rs-fMRI) connectivity measures as diagnostic biomarkers for ASD and investigated which connectivity features are predictive of a diagnosis. Methods Rs-fMRI scans from 59 high functioning males with ASD and 59 age- and IQ-matched typically developing (TD) males were used to build a series of machine learning classifiers. Classification features were obtained using 3 sets of brain regions. Another set of classifiers was built from participants' scores on behavioral metrics. An additional age and IQ-matched cohort of 178 individuals (89 ASD; 89 TD) from the Autism Brain Imaging Data Exchange (ABIDE) open-access dataset (http://fcon_1000.projects.nitrc.org/indi/abide/) were included for replication. Results High classification accuracy was achieved through several rs-fMRI methods (peak accuracy 76.67%). However, classification via behavioral measures consistently surpassed rs-fMRI classifiers (peak accuracy 95.19%). The class probability estimates, P(ASD|fMRI data), from brain-based classifiers significantly correlated with scores on a measure of social functioning, the Social Responsiveness Scale (SRS), as did the most informative features from 2 of the 3 sets of brain-based features. The most informative connections predominantly originated from regions strongly associated with social functioning. Conclusions While individuals can be classified as having ASD with statistically significant accuracy from their rs-fMRI scans alone, this method falls short of biomarker standards. Classification methods provided further evidence that ASD functional connectivity is characterized by dysfunction of large-scale functional networks, particularly those involved in social information processing. PMID:25685703

Plitt, Mark; Barnes, Kelly Anne; Martin, Alex

2014-01-01

132

CT-based quantitative SPECT for the radionuclide 201Tl: experimental validation and a standardized uptake value for brain tumour patients  

PubMed Central

Abstract We have previously reported on a method for reconstructing quantitative data from 99mTc single photon emission computed tomography (SPECT) images based on corrections derived from X-ray computed tomography, producing accurate results in both experimental and clinical studies. This has been extended for use with the radionuclide 201Tl. Accuracy was evaluated with experimental phantom studies, including corrections for partial volume effects where necessary. The quantitative technique was used to derive standardized uptake values (SUVs) for 201Tl evaluation of brain tumours. A preliminary study was performed on 26 patients using 201Tl SPECT scans to assess residual tumour after surgery and then to monitor response to treatment, with a follow-up time of 18 months. Measures of SUVmax were made following quantitative processing of the data and using a threshold grown volume of interest around the tumour. Phantom studies resulted in the calculation of concentration values consistently within 4% of true values. No continuous relation was found between SUVmax (post-resection) and patient survival. Choosing an SUVmax cut-off of 1.5 demonstrated a difference in survival between the 2 groups of patients after surgery. Patients with an SUVmax <1.5 had a 70% survival rate over the first 10 months, compared with a 47% survival rate for those with SUVmax >1.5. This difference did not achieve significance, most likely due to the small study numbers. By 18 months follow-up this difference had reduced, with corresponding survival rates of 40% and 27%, respectively. Although this study involves only a small cohort, it has succeeded in demonstrating the possibility of an SUV measure for SPECT to help monitor response to treatment of brain tumours and predict survival. PMID:22375306

Bailey, Dale; Schembri, Geoff; Baldock, Clive

2012-01-01

133

Wireless brain-machine interface using EEG and EOG: brain wave classification and robot control  

NASA Astrophysics Data System (ADS)

A brain-machine interface (BMI) links a user's brain activity directly to an external device. It enables a person to control devices using only thought. Hence, it has gained significant interest in the design of assistive devices and systems for people with disabilities. In addition, BMI has also been proposed to replace humans with robots in the performance of dangerous tasks like explosives handling/diffusing, hazardous materials handling, fire fighting etc. There are mainly two types of BMI based on the measurement method of brain activity; invasive and non-invasive. Invasive BMI can provide pristine signals but it is expensive and surgery may lead to undesirable side effects. Recent advances in non-invasive BMI have opened the possibility of generating robust control signals from noisy brain activity signals like EEG and EOG. A practical implementation of a non-invasive BMI such as robot control requires: acquisition of brain signals with a robust wearable unit, noise filtering and signal processing, identification and extraction of relevant brain wave features and finally, an algorithm to determine control signals based on the wave features. In this work, we developed a wireless brain-machine interface with a small platform and established a BMI that can be used to control the movement of a robot by using the extracted features of the EEG and EOG signals. The system records and classifies EEG as alpha, beta, delta, and theta waves. The classified brain waves are then used to define the level of attention. The acceleration and deceleration or stopping of the robot is controlled based on the attention level of the wearer. In addition, the left and right movements of eye ball control the direction of the robot.

Oh, Sechang; Kumar, Prashanth S.; Kwon, Hyeokjun; Varadan, Vijay K.

2012-04-01

134

Imaging of sinonasal tumours  

PubMed Central

Abstract More than 70 benign and malignant sinonasal tumours and tumour-like conditions have been described. However, sinonasal tumours are rare, and sinonasal cancers comprise only 3% of all head and neck cancers and 1% of all malignancies, with a peak incidence in the 5th to 7th decades and with a male preponderance. The early symptoms and imaging findings of sinonasal tumours are similar to rhinosinusitis with runny and stuffy nose, lacrimation and epistaxis and therefore neglected both by the patients and doctors. When late symptoms such as anosmia, visual disturbances, cranial neuropathy (Cn II, IV, V, VI) or facial swelling appear, the patient is referred to sinonasal endoscopy or imaging. At the time of correct diagnosis more than half of the tumours have reached an advanced stage with a poor prognostic outcome. Even if imaging is performed in the early stages, a radiologist inexperienced with sinonasal anatomy and tumour features may easily interpret early signs of a malignant tumour as rhinosinusitis or a lesion that does not require follow-up. This article presents the imaging findings in some of the most common benign and malignant sinonasal tumours, and the TNM classification and staging of sinonasal carcinomas. PMID:22571851

2012-01-01

135

Spatial cluster analysis of nanoscopically mapped serotonin receptors for classification of fixed brain tissue  

NASA Astrophysics Data System (ADS)

We present a cluster spatial analysis method using nanoscopic dSTORM images to determine changes in protein cluster distributions within brain tissue. Such methods are suitable to investigate human brain tissue and will help to achieve a deeper understanding of brain disease along with aiding drug development. Human brain tissue samples are usually treated postmortem via standard fixation protocols, which are established in clinical laboratories. Therefore, our localization microscopy-based method was adapted to characterize protein density and protein cluster localization in samples fixed using different protocols followed by common fluorescent immunohistochemistry techniques. The localization microscopy allows nanoscopic mapping of serotonin 5-HT1A receptor groups within a two-dimensional image of a brain tissue slice. These nanoscopically mapped proteins can be confined to clusters by applying the proposed statistical spatial analysis. Selected features of such clusters were subsequently used to characterize and classify the tissue. Samples were obtained from different types of patients, fixed with different preparation methods, and finally stored in a human tissue bank. To verify the proposed method, samples of a cryopreserved healthy brain have been compared with epitope-retrieved and paraffin-fixed tissues. Furthermore, samples of healthy brain tissues were compared with data obtained from patients suffering from mental illnesses (e.g., major depressive disorder). Our work demonstrates the applicability of localization microscopy and image analysis methods for comparison and classification of human brain tissues at a nanoscopic level. Furthermore, the presented workflow marks a unique technological advance in the characterization of protein distributions in brain tissue sections.

Sams, Michael; Silye, Rene; Göhring, Janett; Muresan, Leila; Schilcher, Kurt; Jacak, Jaroslaw

2014-01-01

136

New KF-PP-SVM classification method for EEG in brain-computer interfaces.  

PubMed

Classification methods are a crucial direction in the current study of brain-computer interfaces (BCIs). To improve the classification accuracy for electroencephalogram (EEG) signals, a novel KF-PP-SVM (kernel fisher, posterior probability, and support vector machine) classification method is developed. Its detailed process entails the use of common spatial patterns to obtain features, based on which the within-class scatter is calculated. Then the scatter is added into the kernel function of a radial basis function to construct a new kernel function. This new kernel is integrated into the SVM to obtain a new classification model. Finally, the output of SVM is calculated based on posterior probability and the final recognition result is obtained. To evaluate the effectiveness of the proposed KF-PP-SVM method, EEG data collected from laboratory are processed with four different classification schemes (KF-PP-SVM, KF-SVM, PP-SVM, and SVM). The results showed that the overall average improvements arising from the use of the KF-PP-SVM scheme as opposed to KF-SVM, PP-SVM and SVM schemes are 2.49%, 5.83 % and 6.49 % respectively. PMID:25227081

Yang, Banghua; Han, Zhijun; Zan, Peng; Wang, Qian

2014-01-01

137

Fast and accurate water content and T2* mapping in brain tumours localised with FET-PET  

NASA Astrophysics Data System (ADS)

The availability of combined MR-PET scanners opens new opportunities for the characterisation of tumour environment. In this study, water content and relaxation properties of glioblastoma were investigated in five patients using advanced MRI. The region containing metabolically active tumour tissue was defined by simultaneously measured FET-PET uptake. The mean value of water content in tumour tissue - obtained noninvasively with high precision and accuracy for the first time - amounted to 84.5%, similar to the value for normal grey matter. Constancy of water content contrasted with a large variability of T2* values in tumour tissue, qualitatively related to the magnetic inhomogeneity of tissue created by blood vessels and/or microbleeds. The quantitative MRI protocol takes 71/2 > min of measurement time and is proposed for extended clinical use.

Oros-Peusquens, A.-M.; Keil, F.; Langen, K. J.; Herzog, H.; Stoffels, G.; Weiss, C.; Shah, N. J.

2014-01-01

138

Intracranial tumours in the first 18 months of life  

Microsoft Academic Search

There are few population-based studies of intracranial tumours in children. This study examines 93 brain tumours in children up to 18 months of age from over 800 childhood central nervous system tumours reported to the Manchester Children's Tumour Registry during the period 1953–1987. The incidence was 1 per 25 000 live births. Of these tumours, 85% were malignant. The three

R. Kumar; I. H. Tekkök; R. A. C. Jones

1990-01-01

139

A comparative study of feature extraction and blind source separation of independent component analysis (ICA) on childhood brain tumour 1H magnetic resonance spectra.  

PubMed

Independent component analysis (ICA) has the potential of determining automatically the metabolite signals which make up MR spectra. However, the reliability with which this is accomplished and the optimal approach for investigating in vivo MRS have not been determined. Furthermore, the properties of ICA in brain tumour MRS with respect to dataset size and data quality have not been systematically explored. The two common techniques for applying ICA, blind source separation (BSS) and feature extraction (FE) were examined in this study using simulated data and the findings confirmed on patient data. Short echo time (TE 30 ms), low and high field (1.5 and 3 T) in vivo brain tumour MR spectra of childhood astrocytoma, ependymoma and medulloblastoma were generated by using a quantum mechanical simulator with ten metabolite and lipid components. Patient data (TE 30 ms, 1.5 T) were acquired from children with brain tumours. ICA of simulated data shows that individual metabolite components can be extracted from a set of MRS data. The BSS method generates independent components with a closer correlation to the original metabolite and lipid components than the FE method when the number of spectra in the dataset is small. The experiments also show that stable results are achieved with 300 MRS at an SNR equal to 10. The FE method is relatively insensitive to different ranges of full width at half maximum (FWHM) (from 0 to 3 Hz), whereas the BSS method degrades on increasing the range of FWHM. The peak frequency variations do not affect the results within the range of +/-0.08 ppm for the FE method, and +/-0.05 ppm for the BSS method. When the methods were applied to the patient dataset, results consistent with the synthesized experiments were obtained. PMID:19431141

Hao, Jie; Zou, Xin; Wilson, Martin P; Davies, Nigel P; Sun, Yu; Peet, Andrew C; Arvanitis, Theodoros N

2009-10-01

140

Classification of mathematics deficiency using shape and scale analysis of 3D brain structures  

NASA Astrophysics Data System (ADS)

We investigate the use of a recent technique for shape analysis of brain substructures in identifying learning disabilities in third-grade children. This Riemannian technique provides a quantification of differences in shapes of parameterized surfaces, using a distance that is invariant to rigid motions and re-parameterizations. Additionally, it provides an optimal registration across surfaces for improved matching and comparisons. We utilize an efficient gradient based method to obtain the optimal re-parameterizations of surfaces. In this study we consider 20 different substructures in the human brain and correlate the differences in their shapes with abnormalities manifested in deficiency of mathematical skills in 106 subjects. The selection of these structures is motivated in part by the past links between their shapes and cognitive skills, albeit in broader contexts. We have studied the use of both individual substructures and multiple structures jointly for disease classification. Using a leave-one-out nearest neighbor classifier, we obtained a 62.3% classification rate based on the shape of the left hippocampus. The use of multiple structures resulted in an improved classification rate of 71.4%.

Kurtek, Sebastian; Klassen, Eric; Gore, John C.; Ding, Zhaohua; Srivastava, Anuj

2011-03-01

141

5-Aminolevulinic Acid Induced Endogenous Porphyrin Fluorescence in 9L and C6 Brain Tumours and in the Normal Rat Brain  

Microsoft Academic Search

Summary  \\u000a A new approach in photodynamic therapy is the use of endogenous porphyrins for sensitisation of tumours to light. The induction\\u000a of endogenous porphyrins after intravenous injection of 5-aminolevulinic acid (ALA, 200 mg kg–1 was studied in 23 rats, bearing intracranial 9L or C6 tumours. After 0, 2, 4, 6, 8, and 22 hours the rats were sacrificed\\u000a and the

K. M. Hebeda; A. E. Saarnak; M. Olivo; H. J. C. M. Sterenborg; J. G. Wolbers

1998-01-01

142

Feed-forward hierarchical model of the ventral visual stream applied to functional brain image classification.  

PubMed

Functional brain imaging is a common tool in monitoring the progression of neurodegenerative and neurological disorders. Identifying functional brain imaging derived features that can accurately detect neurological disease is of primary importance to the medical community. Research in computer vision techniques to identify objects in photographs have reported high accuracies in that domain, but their direct applicability to identifying disease in functional imaging is still under investigation in the medical community. In particular, Serre et al. (: In: IEEE Conference on Computer Vision and Pattern Recognition (CVPR-05). pp 994-1000) introduced a biophysically inspired filtering method emulating visual processing in striate cortex which they applied to perform object recognition in photographs. In this work, the model described by Serre et al. [2005] is extended to three-dimensional volumetric images to perform signal detection in functional brain imaging (PET, SPECT). The filter outputs are used to train both neural network and logistic regression classifiers and tested on two distinct datasets: ADNI Alzheimer's disease 2-deoxy-D-glucose (FDG) PET and National Football League players Tc99m HMPAO SPECT. The filtering pipeline is analyzed to identify which steps are most important for classification accuracy. Our results compare favorably with other published classification results and outperform those of a blinded expert human rater, suggesting the utility of this approach. PMID:22847891

Keator, David B; Fallon, James H; Lakatos, Anita; Fowlkes, Charless C; Potkin, Steven G; Ihler, Alexander

2014-01-01

143

Neuropsychological Assessment of Individuals with Brain Tumor: Comparison of Approaches Used in the Classification of Impairment  

PubMed Central

Approaches to classifying neuropsychological impairment after brain tumor vary according to testing level (individual tests, domains, or global index) and source of reference (i.e., norms, controls, and pre-morbid functioning). This study aimed to compare rates of impairment according to different classification approaches. Participants were 44 individuals (57% female) with a primary brain tumor diagnosis (mean age?=?45.6?years) and 44 matched control participants (59% female, mean age?=?44.5?years). All participants completed a test battery that assesses pre-morbid IQ (Wechsler adult reading test), attention/processing speed (digit span, trail making test A), memory (Hopkins verbal learning test-revised, Rey–Osterrieth complex figure-recall), and executive function (trail making test B, Rey–Osterrieth complex figure copy, controlled oral word association test). Results indicated that across the different sources of reference, 86–93% of participants were classified as impaired at a test-specific level, 61–73% were classified as impaired at a domain-specific level, and 32–50% were classified as impaired at a global level. Rates of impairment did not significantly differ according to source of reference (p?>?0.05); however, at the individual participant level, classification based on estimated pre-morbid IQ was often inconsistent with classification based on the norms or controls. Participants with brain tumor performed significantly poorer than matched controls on tests of neuropsychological functioning, including executive function (p?=?0.001) and memory (p??0.05). These results highlight the need to examine individuals’ performance across a multi-faceted neuropsychological test battery to avoid over- or under-estimation of impairment.

Dwan, Toni Maree; Ownsworth, Tamara; Chambers, Suzanne; Walker, David G.; Shum, David H. K.

2015-01-01

144

Neuropsychological assessment of individuals with brain tumor: comparison of approaches used in the classification of impairment.  

PubMed

Approaches to classifying neuropsychological impairment after brain tumor vary according to testing level (individual tests, domains, or global index) and source of reference (i.e., norms, controls, and pre-morbid functioning). This study aimed to compare rates of impairment according to different classification approaches. Participants were 44 individuals (57% female) with a primary brain tumor diagnosis (mean age?=?45.6?years) and 44 matched control participants (59% female, mean age?=?44.5?years). All participants completed a test battery that assesses pre-morbid IQ (Wechsler adult reading test), attention/processing speed (digit span, trail making test A), memory (Hopkins verbal learning test-revised, Rey-Osterrieth complex figure-recall), and executive function (trail making test B, Rey-Osterrieth complex figure copy, controlled oral word association test). Results indicated that across the different sources of reference, 86-93% of participants were classified as impaired at a test-specific level, 61-73% were classified as impaired at a domain-specific level, and 32-50% were classified as impaired at a global level. Rates of impairment did not significantly differ according to source of reference (p?>?0.05); however, at the individual participant level, classification based on estimated pre-morbid IQ was often inconsistent with classification based on the norms or controls. Participants with brain tumor performed significantly poorer than matched controls on tests of neuropsychological functioning, including executive function (p?=?0.001) and memory (p??0.05). These results highlight the need to examine individuals' performance across a multi-faceted neuropsychological test battery to avoid over- or under-estimation of impairment. PMID:25815271

Dwan, Toni Maree; Ownsworth, Tamara; Chambers, Suzanne; Walker, David G; Shum, David H K

2015-01-01

145

Case-control study of the association between malignant brain tumours diagnosed between 2007 and 2009 and mobile and cordless phone use.  

PubMed

Previous studies have shown a consistent association between long-term use of mobile and cordless phones and glioma and acoustic neuroma, but not for meningioma. When used these phones emit radiofrequency electromagnetic fields (RF-EMFs) and the brain is the main target organ for the handheld phone. The International Agency for Research on Cancer (IARC) classified in May, 2011 RF-EMF as a group 2B, i.e. a 'possible' human carcinogen. The aim of this study was to further explore the relationship between especially long-term (>10 years) use of wireless phones and the development of malignant brain tumours. We conducted a new case-control study of brain tumour cases of both genders aged 18-75 years and diagnosed during 2007-2009. One population-based control matched on gender and age (within 5 years) was used to each case. Here, we report on malignant cases including all available controls. Exposures on e.g. use of mobile phones and cordless phones were assessed by a self-administered questionnaire. Unconditional logistic regression analysis was performed, adjusting for age, gender, year of diagnosis and socio-economic index using the whole control sample. Of the cases with a malignant brain tumour, 87% (n=593) participated, and 85% (n=1,368) of controls in the whole study answered the questionnaire. The odds ratio (OR) for mobile phone use of the analogue type was 1.8, 95% confidence interval (CI)=1.04?3.3, increasing with >25 years of latency (time since first exposure) to an OR=3.3, 95% CI=1.6-6.9. Digital 2G mobile phone use rendered an OR=1.6, 95% CI=0.996-2.7, increasing with latency >15-20 years to an OR=2.1, 95% CI=1.2-3.6. The results for cordless phone use were OR=1.7, 95% CI=1.1-2.9, and, for latency of 15-20 years, the OR=2.1, 95% CI=1.2-3.8. Few participants had used a cordless phone for >20-25 years. Digital type of wireless phones (2G and 3G mobile phones, cordless phones) gave increased risk with latency >1-5 years, then a lower risk in the following latency groups, but again increasing risk with latency >15-20 years. Ipsilateral use resulted in a higher risk than contralateral mobile and cordless phone use. Higher ORs were calculated for tumours in the temporal and overlapping lobes. Using the meningioma cases in the same study as reference entity gave somewhat higher ORs indicating that the results were unlikely to be explained by recall or observational bias. This study confirmed previous results of an association between mobile and cordless phone use and malignant brain tumours. These findings provide support for the hypothesis that RF-EMFs play a role both in the initiation and promotion stages of carcinogenesis. PMID:24064953

Hardell, Lennart; Carlberg, Michael; Söderqvist, Fredrik; Mild, Kjell Hansson

2013-12-01

146

Canadian Study of Determinants of Endometabolic Health in ChIlDrEn (CanDECIDE study): a cohort study protocol examining the mechanisms of obesity in survivors of childhood brain tumours  

PubMed Central

Background Childhood obesity has reached epidemic proportions and is impacting children's health globally. In adults, obesity is associated with chronic low-grade inflammation that leads to insulin resistance, which is one of the important mechanisms through which dysregulation of metabolism occurs. There is limited information available about the contribution of inflammation to metabolic health in obese children, and how individual and lifestyle factors impact this risk. One of the paediatric groups at risk of higher rates of obesity includes the survivors of childhood brain tumours. The aim of this study was to evaluate the mechanisms that contribute to inflammation in obese survivors of childhood brain tumours. Methods and analysis This is a prospective cohort study. We will recruit lean and obese survivors of childhood brain tumours, and a control group composed of lean and obese children with no history of tumours. We will measure circulating and urinary cytokine levels and cytokine gene expression in monocytes. In addition, the methylation patterns of cytokine genes and that of toll-like receptor genes will be evaluated. These will be correlated with individual and lifestyle factors including age, sex, ethnicity, puberty, body mass index, fasting lipid levels, insulin sensitivity, diet, exercise, sleep, stress and built environment. The sample size calculation showed that we need 25 participants per arm Ethics and dissemination This study has received ethics approval from the institutional review board. Once completed, we will publish this work in peer-reviewed journals and share the findings in presentations and posters in meetings. Discussion This study will permit the interrogation of inflammation as a contributor to obesity and its complications in obese survivors of childhood brain tumours and compare them with lean survivors and lean and obese controls with no history of tumours, which may help identify therapeutic and preventative interventions to combat the rising tide of obesity. PMID:23794554

Samaan, M Constantine; Thabane, Lehana; Burrow, Sarah; Dillenburg, Rejane F; Scheinemann, Katrin

2013-01-01

147

Hand posture classification using electrocorticography signals in the gamma band over human sensorimotor brain areas  

NASA Astrophysics Data System (ADS)

Objective. Brain-machine interface systems translate recorded neural signals into command signals for assistive technology. In individuals with upper limb amputation or cervical spinal cord injury, the restoration of a useful hand grasp could significantly improve daily function. We sought to determine if electrocorticographic (ECoG) signals contain sufficient information to select among multiple hand postures for a prosthetic hand, orthotic, or functional electrical stimulation system.Approach. We recorded ECoG signals from subdural macro- and microelectrodes implanted in motor areas of three participants who were undergoing inpatient monitoring for diagnosis and treatment of intractable epilepsy. Participants performed five distinct isometric hand postures, as well as four distinct finger movements. Several control experiments were attempted in order to remove sensory information from the classification results. Online experiments were performed with two participants. Main results. Classification rates were 68%, 84% and 81% for correct identification of 5 isometric hand postures offline. Using 3 potential controls for removing sensory signals, error rates were approximately doubled on average (2.1×). A similar increase in errors (2.6×) was noted when the participant was asked to make simultaneous wrist movements along with the hand postures. In online experiments, fist versus rest was successfully classified on 97% of trials; the classification output drove a prosthetic hand. Online classification performance for a larger number of hand postures remained above chance, but substantially below offline performance. In addition, the long integration windows used would preclude the use of decoded signals for control of a BCI system. Significance. These results suggest that ECoG is a plausible source of command signals for prosthetic grasp selection. Overall, avenues remain for improvement through better electrode designs and placement, better participant training, and characterization of non-stationarities such that ECoG could be a viable signal source for grasp control for amputees or individuals with paralysis.

Chestek, Cynthia A.; Gilja, Vikash; Blabe, Christine H.; Foster, Brett L.; Shenoy, Krishna V.; Parvizi, Josef; Henderson, Jaimie M.

2013-04-01

148

Hand posture classification using electrocorticography signals in the gamma band over human sensorimotor brain areas  

PubMed Central

Objective Brain machine interface systems translate recorded neural signals into command signals for assistive technology. In individuals with upper limb amputation or cervical spinal cord injury, the restoration of a useful hand grasp could significantly improve daily function. We sought to determine if electrocorticographic (ECoG) signals contain sufficient information to select among multiple hand postures for a prosthetic hand, orthotic, or functional electrical stimulation system. Approach We recorded ECoG signals from subdural macro- and microelectrodes implanted in motor areas of three participants who were undergoing inpatient monitoring for diagnosis and treatment of intractable epilepsy. Participants performed 5 distinct isometric hand postures, as well as 4 distinct finger movements. Several control experiments were attempted in order to remove sensory information from the classification results. Online experiments were performed with 2 participants. Main Results Classification rates were 68%, 84%, and 81% for correct identification of 5 isometric hand postures offline. Using 3 potential controls for removing sensory signals, error rates were approximately doubled on average (2.1×). A similar increase in errors (2.6×) was noted when the participant was asked to make simultaneous wrist movements along with the hand postures. In online experiments, fist versus rest was successfully classified on 97% of trials; the classification output drove a prosthetic hand. Online classification performance for a larger number of hand postures remained above chance, but substantially below offline performance. In addition, the long integration windows used would preclude the use of decoded signals for control of a BCI system. Significance These results suggest that ECoG is a plausible source of command signals for prosthetic grasp selection. Overall, avenues remain for improvement through better electrode designs and placement, better participant training, and characterization of non-stationarities such that ECoG could be a viable signal source for grasp control for amputees or individuals with paralysis. PMID:23369953

Chestek, Cynthia A.; Gilja, Vikash; Blabe, Christine H.; Foster, Brett L.; Shenoy, Krishna V.; Parvizi, Josef; Henderson, Jaimie M.

2013-01-01

149

8 107 9654321Issue 07 April 2010 This issue: 1 Nuclear physics promises earlier detection of brain tumours with just one scan 3 CLASP Challenge Led Knowledge Exchange call to meet Challenges  

E-print Network

tumours with just one scan 3 CLASP Challenge Led Knowledge Exchange call to meet Challenges in the Medical Technology could revolutionise optical and laser systems 10 Networks of sensors Time taken to detect brain of Liverpool with the Nuclear Physics Group and Technology departments at the Science and Technology Facilities

150

Improved CSF classification and lesion detection in MR brain images with multiple sclerosis  

NASA Astrophysics Data System (ADS)

The study deals with the challenging task of automatic segmentation of MR brain images with multiple sclerosis lesions (MSL). Multi-Channel data is used, including "fast fluid attenuated inversion recovery" (fast FLAIR or FF), and statistical modeling tools are developed, in order to improve cerebrospinal fluid (CSF) classification and to detect MSL. Two new concepts are proposed for use within an EM framework. The first concept is the integration of prior knowledge as it relates to tissue behavior in different MRI modalities, with special attention given to the FF modality. The second concept deals with running the algorithm on a subset of the input that is most likely to be noise- and artifact-free data. This enables a more reliable learning of the Gaussian mixture model (GMM) parameters for brain tissue statistics. The proposed method focuses on the problematic CSF intensity distribution, which is a key to improved overall segmentation and lesion detection. A level-set based active contour stage is performed for lesion delineation, using gradient and shape properties combined with previously learned region intensity statistics. In the proposed scheme there is no need for preregistration of an atlas, a common characteristic in brain segmentation schemes. Experimental results on real data are presented.

Wolff, Yulian; Miron, Shmuel; Achiron, Anat; Greenspan, Hayit

2007-03-01

151

RPA classification has prognostic significance for surgically resected single brain metastasis  

SciTech Connect

Purpose: To retrospectively evaluate prognostic factors that correlate with overall survival among patients with a surgically resected single brain metastasis. Methods and Materials: An Institutional Review Board-approved database of Cleveland Clinic Brain Tumor Institute was queried for patients with a single brain metastasis treated by surgical resection between February 1984 and January 2004. The primary endpoint was overall survival from the date of surgery by the Kaplan-Meier method. Results: A total of 271 patients were included. Statistically significant variables for improved survival on multivariate analysis included age <65 years, lack of extracranial metastases, control of primary tumor, histology (non-small-cell lung carcinoma), and use of stereotactic radiosurgery. The median survival for all patients was 10.2 months. Survival of patients in recursive partitioning analysis (RPA) class 1 was better (21.4 months) than those in RPA class 2 (9.0 months, p < 0.001), RPA class 3 (8.9 months, p = 0.15), or the combined group of RPA classes 2 and 3 (9.0 months, p < 0.001). Patients had a median survival of 10.6 months after documented gross total resection and 8.7 months after subtotal resection, which approached statistical significance (p 0.07). Those who were treated with stereotactic radiosurgery had a median survival of 17.1 months, which was greater than patients who were not treated with stereotactic radiosurgery (8.9 months, p = 0.006). Conclusions: This analysis supports the prognostic significance of the RPA classification in patients with a single brain metastasis who undergo surgical resection and adjuvant therapy. RPA class 1 patients have a very favorable prognosis with a median survival of 21.4 months.

Tendulkar, Rahul D. [Department of Radiation Oncology, Brain Tumor Institute, Cleveland Clinic, Cleveland, OH (United States); Liu, Stephanie W. [Northwestern University Feinberg School of Medicine, Chicago, IL (United States); Barnett, Gene H. [Department of Neurosurgery, Brain Tumor Institute, Cleveland Clinic, Cleveland, OH (United States); Vogelbaum, Michael A. [Department of Neurosurgery, Brain Tumor Institute, Cleveland Clinic, Cleveland, OH (United States); Toms, Steven A. [Department of Neurosurgery, Brain Tumor Institute, Cleveland Clinic, Cleveland, OH (United States); Jin Tao [Department of Biostatistics, Brain Tumor Institute, Cleveland Clinic, Cleveland, OH (United States); Suh, John H. [Department of Radiation Oncology, Brain Tumor Institute, Cleveland Clinic, Cleveland, OH (United States)

2006-11-01

152

Impact of brain tumour location on emotion and personality: a voxel-based lesion-symptom mapping study on mentalization processes.  

PubMed

Patients affected by brain tumours may show behavioural and emotional regulation deficits, sometimes showing flattened affect and sometimes experiencing a true 'change' in personality. However, little evidence is available to the surgeon as to what changes are likely to occur with damage at specific sites, as previous studies have either relied on single cases or provided only limited anatomical specificity, mostly reporting associations rather than dissociations of symptoms. We investigated these aspects in patients undergoing surgery for the removal of cerebral tumours. We argued that many of the problems described can be ascribed to the onset of difficulties in one or more of the different levels of the process of mentalizing (i.e. abstracting and reflecting upon) emotion and intentions, which impacts on everyday behaviour. These were investigated in terms of (i) emotion recognition; (ii) Theory of Mind; (iii) alexithymia; and (iv) self-maturity (personality disorder). We hypothesized that temporo/limbic areas would be critical for processing emotion and intentions at a more perceptual level, while frontal lobe structures would be more critical when higher levels of mentalization/abstraction are required. We administered four different tasks, Task 1: emotion recognition of Ekman faces; Task 2: the Eyes Test (Theory of Mind); Task 3: Toronto Alexithymia Scale; and Task 4: Temperament and Character Inventory (a personality inventory), both immediately before and few days after the operation for the removal of brain tumours in a series of 71 patients (age range: 18-75 years; 33 female) with lesions located in the left or right frontal, temporal and parietal lobes. Lobe-based and voxel-based analysis confirmed that tasks requiring interpretation of emotions and intentions at more basic (less mentalized) levels (Tasks 1 and 2) were more affected by temporo/insular lesions, with emotion recognition (Task 1) being maximally impaired by anterior temporal and amygdala lesions and Task 2 (found to be a 'basic' Theory of Mind task involving only limited mentalization) being mostly impaired by posterior temporoparietal lesions. Tasks relying on higher-level mentalization (Tasks 3 and 4) were maximally affected by prefrontal lesions, with the alexithymia scale (Task 3) being mostly associated with anterior/medial lesions and the self-maturity measure (Task 4) with lateral prefrontal ones. PMID:25027503

Campanella, Fabio; Shallice, Tim; Ius, Tamara; Fabbro, Franco; Skrap, Miran

2014-09-01

153

Comparison of Classification Methods for P300 Brain-Computer Interface on Disabled Subjects  

PubMed Central

We report on tests with a mind typing paradigm based on a P300 brain-computer interface (BCI) on a group of amyotrophic lateral sclerosis (ALS), middle cerebral artery (MCA) stroke, and subarachnoid hemorrhage (SAH) patients, suffering from motor and speech disabilities. We investigate the achieved typing accuracy given the individual patient's disorder, and how it correlates with the type of classifier used. We considered 7 types of classifiers, linear as well as nonlinear ones, and found that, overall, one type of linear classifier yielded a higher classification accuracy. In addition to the selection of the classifier, we also suggest and discuss a number of recommendations to be considered when building a P300-based typing system for disabled subjects. PMID:21941530

Manyakov, Nikolay V.; Chumerin, Nikolay; Combaz, Adrien; Van Hulle, Marc M.

2011-01-01

154

Dysembryoplastic neuroepithelial tumours.  

PubMed

Dysembryoplastic neuroepithelial tumours (DNTs) are a group of supratentorial cortical benignant lesions that superficially resemble mixed oligo-astrocytomas, oligodendrogliomas or astrocytomas. Clinically these tumours are associated with partial seizures beginning before the age of 20 years, with no neurologic deficit and no stigmata of phacomatosis. In the revised WHO classification, DNTs have been incorporated among the category of neuronal and mixed neuronoglial tumours. This classification describes a histologic variant characterized by the following criteria: cortical location, multinodular architecture--the nodule being made of multiple variants looking like astrocytomas, oligodendrogliomas or oligo-astrocytomas, foci of dysplastic cortical disorganization and the presence of a glioneuronal element showing a columnar structure perpendicular to the cortical surface. A study of 14 cases for which only a specific glioneuronal element could be identified demonstrated that this specific element is sufficient for diagnosing DNTs and that the spectrum of DNTs includes a simple form with a unique glioneuronal element. Preoperative imaging follow-up data, in the series of 23 simple and complex forms, indicated that DNTs are perfectly stable. However, these tumours may show a high MIB 1 labeling index. PMID:8293188

Daumas-Duport, C

1993-07-01

155

Brain fingerprinting classification concealed information test detects US Navy military medical information with P300.  

PubMed

A classification concealed information test (CIT) used the "brain fingerprinting" method of applying P300 event-related potential (ERP) in detecting information that is (1) acquired in real life and (2) unique to US Navy experts in military medicine. Military medicine experts and non-experts were asked to push buttons in response to three types of text stimuli. Targets contain known information relevant to military medicine, are identified to subjects as relevant, and require pushing one button. Subjects are told to push another button to all other stimuli. Probes contain concealed information relevant to military medicine, and are not identified to subjects. Irrelevants contain equally plausible, but incorrect/irrelevant information. Error rate was 0%. Median and mean statistical confidences for individual determinations were 99.9% with no indeterminates (results lacking sufficiently high statistical confidence to be classified). We compared error rate and statistical confidence for determinations of both information present and information absent produced by classification CIT (Is a probe ERP more similar to a target or to an irrelevant ERP?) vs. comparison CIT (Does a probe produce a larger ERP than an irrelevant?) using P300 plus the late negative component (LNP; together, P300-MERMER). Comparison CIT produced a significantly higher error rate (20%) and lower statistical confidences: mean 67%; information-absent mean was 28.9%, less than chance (50%). We compared analysis using P300 alone with the P300 + LNP. P300 alone produced the same 0% error rate but significantly lower statistical confidences. These findings add to the evidence that the brain fingerprinting methods as described here provide sufficient conditions to produce less than 1% error rate and greater than 95% median statistical confidence in a CIT on information obtained in the course of real life that is characteristic of individuals with specific training, expertise, or organizational affiliation. PMID:25565941

Farwell, Lawrence A; Richardson, Drew C; Richardson, Graham M; Furedy, John J

2014-01-01

156

Brain fingerprinting classification concealed information test detects US Navy military medical information with P300  

PubMed Central

A classification concealed information test (CIT) used the “brain fingerprinting” method of applying P300 event-related potential (ERP) in detecting information that is (1) acquired in real life and (2) unique to US Navy experts in military medicine. Military medicine experts and non-experts were asked to push buttons in response to three types of text stimuli. Targets contain known information relevant to military medicine, are identified to subjects as relevant, and require pushing one button. Subjects are told to push another button to all other stimuli. Probes contain concealed information relevant to military medicine, and are not identified to subjects. Irrelevants contain equally plausible, but incorrect/irrelevant information. Error rate was 0%. Median and mean statistical confidences for individual determinations were 99.9% with no indeterminates (results lacking sufficiently high statistical confidence to be classified). We compared error rate and statistical confidence for determinations of both information present and information absent produced by classification CIT (Is a probe ERP more similar to a target or to an irrelevant ERP?) vs. comparison CIT (Does a probe produce a larger ERP than an irrelevant?) using P300 plus the late negative component (LNP; together, P300-MERMER). Comparison CIT produced a significantly higher error rate (20%) and lower statistical confidences: mean 67%; information-absent mean was 28.9%, less than chance (50%). We compared analysis using P300 alone with the P300 + LNP. P300 alone produced the same 0% error rate but significantly lower statistical confidences. These findings add to the evidence that the brain fingerprinting methods as described here provide sufficient conditions to produce less than 1% error rate and greater than 95% median statistical confidence in a CIT on information obtained in the course of real life that is characteristic of individuals with specific training, expertise, or organizational affiliation. PMID:25565941

Farwell, Lawrence A.; Richardson, Drew C.; Richardson, Graham M.; Furedy, John J.

2014-01-01

157

ELUCIDATING BRAIN CONNECTIVITY NETWORKS IN MAJOR DEPRESSIVE DISORDER USING CLASSIFICATION-BASED SCORING  

PubMed Central

Graph theory is increasingly used in the field of neuroscience to understand the large-scale network structure of the human brain. There is also considerable interest in applying machine learning techniques in clinical settings, for example, to make diagnoses or predict treatment outcomes. Here we used support-vector machines (SVMs), in conjunction with whole-brain tractography, to identify graph metrics that best differentiate individuals with Major Depressive Disorder (MDD) from nondepressed controls. To do this, we applied a novel feature-scoring procedure that incorporates iterative classifier performance to assess feature robustness. We found that small-worldness, a measure of the balance between global integration and local specialization, most reliably differentiated MDD from nondepressed individuals. Post-hoc regional analyses suggested that heightened connectivity of the subcallosal cingulate gyrus (SCG) in MDDs contributes to these differences. The current study provides a novel way to assess the robustness of classification features and reveals anomalies in large-scale neural networks in MDD. PMID:25580184

Sacchet, Matthew D.; Prasad, Gautam; Foland-Ross, Lara C.; Thompson, Paul M.; Gotlib, Ian H.

2014-01-01

158

Assigning exposure to pesticides and solvents from self?reports collected by a computer assisted personal interview and expert assessment of job codes: the UK Adult Brain Tumour Study  

PubMed Central

Objectives To compare assignment of occupational pesticide and solvent exposure using self?reported data collected by a computer assisted personal interview (CAPI) with exposure based on expert assessment of job codes. To discuss the advantages and disadvantages of using a CAPI to collect individual occupational exposure data. Methods Between 2001 and 2004, 1495 participants were interviewed using a CAPI for a case?control study of adult brain tumours and acoustic neuromas. Two types of occupational data were collected: (1) a full history, including job title from which a job code was assigned from the Standard Occupational Classification; and (2) specific details on pesticide and solvent exposure reported by participants. Study members' experiences of using the CAPI were recorded and advantages and disadvantages summarised. Results Of 7192 jobs recorded, the prevalence of self?reported exposure was 1.3% for pesticides and 11.5% for solvents. Comparing this with exposure expertly assessed from job titles showed 53.6% and 45.8% concordance for pesticides and solvents respectively. Advantages of the CAPI include no data entry stage, automatic input validation, and a reduction in interviewer bias. Disadvantages include an adverse effect on study implementation as a consequence of resources required for programming and difficulties encountered with data management prior to analysis. Conclusions Different methods of exposure assessment derive different exposure levels for pesticide and solvent exposure at work. Agreement between self?reported and expert assessment of exposure was greater for pesticides compared to solvents. The advantages of using a CAPI for the collection of complex data outweigh the disadvantages for interviewers and data quality but using such a method requires extra resources at the study outset. PMID:16556747

Hepworth, S J; Bolton, A; Parslow, R C; van Tongeren, M; Muir, K R; McKinney, P A

2006-01-01

159

Classification  

ERIC Educational Resources Information Center

In this article, Renee Clary and James Wandersee describe the beginnings of "Classification," which lies at the very heart of science and depends upon pattern recognition. Clary and Wandersee approach patterns by first telling the story of the "Linnaean classification system," introduced by Carl Linnacus (1707-1778), who is…

Clary, Renee; Wandersee, James

2013-01-01

160

Diagnosis, classification and grading of canine mammary tumours as a model to study human breast cancer: an Clinico-Cytohistopathological study with environmental factors influencing public health and medicine  

PubMed Central

Background The human “Elston and Ellis grading method” was utilized in dogs with mammary tumor to examine its relation to prognosis in this species, based on a 2-year follow-up period. Although cytopathology is widely used for early diagnosis of human neoplasms, it is not commonly performed in veterinary medicine. Our objectives in this study were to identify cytopathology criteria of malignancy for canine mammary tumors and the frequency of different types of mammary lesions and their relationship with histologic grade was investigated. Another aim of this study was to differentiate the simple and adenocarcinoma tumors from the complex or mixed tumor described by Elston and Ellis grading method. Methods The study was performed in 15 pure or mixed-breed female dogs submitted to surgical resections of mammary tumours. The mammary tumours were excised by simple mastectomy or regional mastectomy, with or without the superficial inguinal lymph nodes. Female dogs were mainly terriers (9 dogs) or mixed (3 dogs), the 3 other animals were a German shepherd, Dachshund and Pekingese. Before surgical excision of the tumour, FNAC was performed using a 0.6 mm diameter needle attached to a 10 ml syringe held in a standard metal syringe holder. The cytological sample was smeared onto a glass slide and either air-dried for May-Grünwald-stain, or ethanol-fixed for Papanicolaou stain and masses were surgically removed, the tumours were grossly examined and tissue samples were fixed in 10%-buffered-formalin and embedded in paraffin. Sections 4 ?m thick were obtained from each sample and H&E stained. Results We obtained a correct cytohistological correlation in 14/15 cases (93.3%) when all cytopathological examinations were considered. Of the 15 cases examined, 2(13.3%) had well-differentiated (grade I), 6(40%) had moderately differentiated (grade II) and 7(46.7%) had poorly differentiated (grade III) tumours. Classification of all canine mammary gland lesions revealed 13(86.7%) malignant and 2(13.3%) benign tumors. The histological examination showed that the most common tumor types of mammary glands in bitches were: complex carcinoma, adenocarcinoma, malignant mixed tumour, benign mixed tumour, simple carcinoma– (5/15; 33.3%), (3/15; 20%), (3/15; 20%) and (2/15;13.3%), respectively. Simple carcinoma and cystic hyperplasia were less common - (1/15; 6.7%), and (1/15; 6.7%), respectively. Moreover, the most often tumors occur in inguinal mammary (60%) and abdominal (27%) glands. Conclusions Our results demonstrate that, because of the similarity of the cytohistopathological findings in the human and canine mammary gland tumours, it is possible to use the same cytopathological criteria applied in human pathology for the diagnosis of canine mammary gland tumours. Furthemoer, routine use of this human grading method would help the clinician to make a more accurate prognosis in the interests of post-surgical management in dogs with mammary carcinomas. Furthermore, this research will allow a more discriminating classification of mammary tumors and probably has a bearing on cytohistopathology, epidemiology, pathogenesis and prognosis. The most often tumors occur in inguinal mammary (60%) and abdominal (27%) glands. This interesting regional difference may be due to a) the duration of the growth before the diagnosis; b) the age of the dogs; and c) high prevelance of unspayed animals. Moreover, the most common type of tumor was complex carcinoma – 33.3% (5 cases). PMID:23937693

2013-01-01

161

Multiclass classification of hemodynamic responses for performance improvement of functional near-infrared spectroscopy-based brain-computer interface  

NASA Astrophysics Data System (ADS)

We improved the performance of a functional near-infrared spectroscopy (fNIRS)-based brain-computer interface based on relatively short task duration and multiclass classification. A custom-built eight-channel fNIRS system was used over the motor cortex areas in both hemispheres to measure the hemodynamic responses evoked by four different motor tasks (overt execution of arm lifting and knee extension for both sides) instead of finger tapping. The hemodynamic responses were classified using the naive Bayes classifier. Among the mean, max, slope, variance, and median of the signal amplitude and the time lag of the signal, several signal features are chosen to obtain highest classification accuracy. Ten runs of threefold cross-validation were conducted, which yielded classification accuracies of 87.1%±2.4% to 95.5%±2.4%, 77.5%±1.9% to 92.4%±3.2%, and 73.8%±3.5% to 91.5%±1.4% for the binary, ternary, and quaternary classifications, respectively. Eight seconds of task duration for obtaining sufficient quaternary classification accuracy was suggested. The bit transfer rate per minute (BPM) based on the quaternary classification accuracy was investigated. A BPM can be achieved from 2.81 to 5.40 bits/min.

Shin, Jaeyoung; Jeong, Jichai

2014-06-01

162

Brain activity-based image classification from rapid serial visual presentation.  

PubMed

We report the design and performance of a brain-computer interface (BCI) system for real-time single-trial binary classification of viewed images based on participant-specific dynamic brain response signatures in high-density (128-channel) electroencephalographic (EEG) data acquired during a rapid serial visual presentation (RSVP) task. Image clips were selected from a broad area image and presented in rapid succession (12/s) in 4.1-s bursts. Participants indicated by subsequent button press whether or not each burst of images included a target airplane feature. Image clip creation and search path selection were designed to maximize user comfort and maintain user awareness of spatial context. Independent component analysis (ICA) was used to extract a set of independent source time-courses and their minimally-redundant low-dimensional informative features in the time and time-frequency amplitude domains from 128-channel EEG data recorded during clip burst presentations in a training session. The naive Bayes fusion of two Fisher discriminant classifiers, computed from the 100 most discriminative time and time-frequency features, respectively, was used to estimate the likelihood that each clip contained a target feature. This estimator was applied online in a subsequent test session. Across eight training/test session pairs from seven participants, median area under the receiver operator characteristic curve, by tenfold cross validation, was 0.97 for within-session and 0.87 for between-session estimates, and was nearly as high (0.83) for targets presented in bursts that participants mistakenly reported to include no target features. PMID:18990647

Bigdely-Shamlo, Nima; Vankov, Andrey; Ramirez, Rey R; Makeig, Scott

2008-10-01

163

Inspection time in patients with intracranial tumours before and after neurosurgery   

E-print Network

Introduction: Many patients with brain tumours experience dysfunction in several cognitive domains. Given the limited survival times of the majority of patients with brain tumours, maintenance or improvement of quality ...

Scotland, Jennifer L

2010-01-01

164

Validation of the RTOG recursive partitioning analysis (RPA) classification for small-cell lung cancer-only brain metastases  

SciTech Connect

Purpose: Radiation Therapy Oncology Group (RTOG) developed a prognostic classification based on a recursive partitioning analysis (RPA) of patient pretreatment characteristics from three completed brain metastases randomized trials. Clinical trials for patients with brain metastases generally exclude small-cell lung cancer (SCLC) cases. We hypothesize that the RPA classes are valid in the setting of SCLC brain metastases. Methods and Materials: A retrospective review of 154 SCLC patients with brain metastases treated between April 1983 and May 2005 was performed. RPA criteria used for class assignment were Karnofsky performance status (KPS), primary tumor status (PT), presence of extracranial metastases (ED), and age. Results: Median survival was 4.9 months, with 4 patients (2.6%) alive at analysis. Median follow-up was 4.7 months (range, 0.3-40.3 months). Median age was 65 (range, 42-85 years). Median KPS was 70 (range, 40-100). Number of patients with controlled PT and no ED was 20 (13%) and with ED, 27 (18%); without controlled PT and ED, 34 (22%) and with ED, 73 (47%). RPA class distribution was: Class I: 8 (5%); Class II: 96 (62%); Class III: 51 (33%). Median survivals (in months) by RPA class were: Class I: 8.6; Class II: 4.2; Class III: 2.3 (p = 0.0023). Conclusions: Survivals for SCLC-only brain metastases replicate the results from the RTOG RPA classification. These classes are therefore valid for brain metastases from SCLC, support the inclusion of SCLC patients in future brain metastases trials, and may also serve as a basis for historical comparisons.

Videtic, Gregory M.M. [Department of Radiation Oncology, Cleveland Clinic Foundation, Cleveland, OH (United States)]. E-mail: videtig@ccf.org; Adelstein, David J. [Department of Medical Oncology, Cleveland Clinic Foundation, Cleveland, OH (United States); Mekhail, Tarek M. [Department of Medical Oncology, Cleveland Clinic Foundation, Cleveland, OH (United States); Rice, Thomas W. [Department of Thoracic Surgery, Cleveland Clinic Foundation, Cleveland, OH (United States); Stevens, Glen H.J. [Brain Tumor Institute, Cleveland Clinic Foundation, Cleveland, OH (United States); Lee, S.-Y. [Department of Radiation Oncology, Cleveland Clinic Foundation, Cleveland, OH (United States); Suh, John H. [Department of Radiation Oncology, Cleveland Clinic Foundation, Cleveland, OH (United States); Brain Tumor Institute, Cleveland Clinic Foundation, Cleveland, OH (United States)

2007-01-01

165

Automated Classification to Predict the Progression of Alzheimer's Disease Using Whole-Brain Volumetry and DTI  

PubMed Central

Objective This study proposes an automated diagnostic method to classify patients with Alzheimer's disease (AD) of degenerative etiology using magnetic resonance imaging (MRI) markers. Methods Twenty-seven patients with subjective memory impairment (SMI), 18 patients with mild cognitive impairment (MCI), and 27 patients with AD participated. MRI protocols included three dimensional brain structural imaging and diffusion tensor imaging to assess the cortical thickness, subcortical volume and white matter integrity. Recursive feature elimination based on support vector machine (SVM) was conducted to determine the most relevant features for classifying abnormal regions and imaging parameters, and then a factor analysis for the top-ranked factors was performed. Subjects were classified using nonlinear SVM. Results Medial temporal regions in AD patients were dominantly detected with cortical thinning and volume atrophy compared with SMI and MCI patients. Damage to white matter integrity was also accredited with decreased fractional anisotropy and increased mean diffusivity (MD) across the three groups. The microscopic damage in the subcortical gray matter was reflected in increased MD. Classification accuracy between pairs of groups (SMI vs. MCI, MCI vs. AD, SMI vs. AD) and among all three groups were 84.4% (±13.8), 86.9% (±10.5), 96.3% (±4.6), and 70.5% (±11.5), respectively. Conclusion This proposed method may be a potential tool to diagnose AD pathology with the current clinical criteria. PMID:25670951

Jung, Won Beom; Lee, Young Min; Kim, Young Hoon

2015-01-01

166

CLASSIFICATION  

NSDL National Science Digital Library

Project Overview: Classification is grouping similar objects together. When you go into a grocery store, you see fresh fruits and vegetables, frozen food, cereal, and pet suplies in different aisles. Imagine how difficult life would be if you went into a store, and the aisles were not labeled to tell you where to find the items! You don't have to be a scientist to use classification! You use classification when you group your IPOD music into different genres and when you divide your dark colored clothing from light colors to do laundry. You might even use it to sort Halloween candy into 4 groups: chocolate candy, hard candy, chewy candy, and gum. The science of classification is called taxonomy. Taxonomy classifies organisms based on evolutionary relationships and describes and names organisms with a two-part name: genus and species. Scientists use taxonomy to identify unknown organisms by using books called field guides or by using taxonomic keys (also called dichomotous keys). Project Objective: As a class,you will be previewing and answering some questions about some classification resources to learn how to use a dichotomous key, how to key a specimen, and to help you write your own dichotomous key for school items. Project: Get a sheet of notebook paper and pencil and refer to the websites to find the answers to the questions. One way to classify objects is to create a "tree" to group similar objects together.Open hierarchical classfication of objects to the second page and find the diagram of common household objects. See how all the ...

Mrs. Ballew

2010-10-17

167

Liver tumours.  

PubMed

Humans are remarkably resistant to many carcinogens that readily produce liver tumours in rodents, particularly the rat. The neoplastic process has been extensively studied in animal experiments, but little is known so far of how it evolves in humans. Few drugs have been shown to cause liver tumours in humans, and the risk appears to be low. The best-known examples are C17-alkylated or ethinylated gonadal sex steroids. Oral contraceptives have now been in use by millions for thirty years, but only a few hundred cases at most of liver cell adenoma have been observed. The role of these substances in liver cell carcinoma remains controversial, and the evidence is weaker still in relation to focal nodular hyperplasia and other tumour-like conditions. Anabolic-androgenic steroids stand out as the major cause of peliosis, but liver cell tumours induced by them seem to be adenomas and not carcinomas as originally suggested. The effect that both oral contraceptives and anabolic-androgenic steroids have on liver vasculature is of great clinical importance as the most important complication of liver tumours is rupture, leading to life-threatening haemorrhage. For this reason, liver tumours arising in users of these drugs should be removed whenever feasible. Thorium dioxide will remain a risk factor for the development of angiosarcoma, liver cell carcinoma and bile duct carcinoma for some time yet, and the number of patients who have been exposed is high--tens of thousands at least. The evidence of a carcinogenic role for many other drugs is anecdotal or weak. Neoplasia in the liver seems to be the least important side-effect of drugs in clinical use. PMID:2841989

Anthony, P P

1988-04-01

168

Ependymoma in children under the age of 3 years: a report from the Canadian Pediatric Brain Tumour Consortium.  

PubMed

The determination of optimal therapy for ependymoma (EP) in infants is ongoing. We describe the incidence, management and outcomes of Canadian infants with EP to discern potential future research questions. Of 579 cases registered in a national database of children <36 months of age diagnosed with a brain tumor from 1990 to 2005, inclusive, 75 (13 %) were EP. These cases were analyzed. A mean annual age-adjusted incidence rate of 4.6 per 100,000 children years was calculated. The male:female ratio was 1.77. Of the tumors, 80 % were infratentorial in location, 67 % were WHO grade II histology, and 29 % were metastatic at diagnosis. All patients underwent a surgical procedure. A complete resection of the tumor was achieved in 56 % of the cases; 43 % of these patients survive while 36 % of the patients with tumors less than completely resected survive. Initial therapy consisted of surgery alone in 23 % of patients, or surgery plus chemotherapy (37 %), radiation therapy (RT; 19 %), or both (21 %). Any use of RT increased with patient age. The 5-year EFS rates for patients in each of the four treatment groups was 22, 11.5, 46.2 and 64.8 %, respectively. For all patients the median survival was 63 ± 6 months and 5-year overall survival was 55 ± 6 %. Patients treated with surgery and chemotherapy alone were younger and had a lower rate of survival than older patients who were more often treated with radiation therapy containing regimens. Further study is needed to determine which patients are optimally served with these treatment modalities. PMID:24532240

Purdy, Eve; Johnston, Donna L; Bartels, Ute; Fryer, Chris; Carret, Anne-Sophie; Crooks, Bruce; Eisenstat, David D; Lafay-Cousin, Lucie; Larouche, Valerie; Wilson, Beverly; Zelcer, Shayna; Silva, Mariana; Bouffet, Eric; Keene, Daniel; Strother, Douglas R

2014-04-01

169

Classification  

NASA Astrophysics Data System (ADS)

A supervised learning task involves constructing a mapping from input data (normally described by several features) to the appropriate outputs. A set of training examples— examples with known output values—is used by a learning algorithm to generate a model. This model is intended to approximate the mapping between the inputs and outputs. This model can be used to generate predicted outputs for inputs that have not been seen before. Within supervised learning, one type of task is a classification learning task, in which each output is one or more classes to which the input belongs. For example, we may have data consisting of observations of sunspots. In a classification learning task, our goal may be to learn to classify sunspots into one of several types. Each example may correspond to one candidate sunspot with various measurements or just an image. A learning algorithm would use the supplied examples to generate a model that approximates the mapping between each supplied set of measurements and the type of sunspot. This model can then be used to classify previously unseen sunspots based on the candidate’s measurements. The generalization performance of a learned model (how closely the target outputs and the model’s predicted outputs agree for patterns that have not been presented to the learning algorithm) would provide an indication of how well the model has learned the desired mapping. More formally, a classification learning algorithm L takes a training set T as its input. The training set consists of |T| examples or instances. It is assumed that there is a probability distribution D from which all training examples are drawn independently—that is, all the training examples are independently and identically distributed (i.i.d.). The ith training example is of the form (x_i, y_i), where x_i is a vector of values of several features and y_i represents the class to be predicted.* In the sunspot classification example given above, each training example would represent one sunspot’s classification (y_i) and the corresponding set of measurements (x_i). The output of a supervised learning algorithm is a model h that approximates the unknown mapping from the inputs to the outputs. In our example, h would map from the sunspot measurements to the type of sunspot. We may have a test set S—a set of examples not used in training that we use to test how well the model h predicts the outputs on new examples. Just as with the examples in T, the examples in S are assumed to be independent and identically distributed (i.i.d.) draws from the distribution D. We measure the error of h on the test set as the proportion of test cases that h misclassifies: 1/|S| Sigma(x,y union S)[I(h(x)!= y)] where I(v) is the indicator function—it returns 1 if v is true and 0 otherwise. In our sunspot classification example, we would identify additional examples of sunspots that were not used in generating the model, and use these to determine how accurate the model is—the fraction of the test samples that the model classifies correctly. An example of a classification model is the decision tree shown in Figure 23.1. We will discuss the decision tree learning algorithm in more detail later—for now, we assume that, given a training set with examples of sunspots, this decision tree is derived. This can be used to classify previously unseen examples of sunpots. For example, if a new sunspot’s inputs indicate that its "Group Length" is in the range 10-15, then the decision tree would classify the sunspot as being of type “E,” whereas if the "Group Length" is "NULL," the "Magnetic Type" is "bipolar," and the "Penumbra" is "rudimentary," then it would be classified as type "C." In this chapter, we will add to the above description of classification problems. We will discuss decision trees and several other classification models. In particular, we will discuss the learning algorithms that generate these classification models, how to use them to classify new

Oza, Nikunj

2012-03-01

170

Classification  

NASA Technical Reports Server (NTRS)

A supervised learning task involves constructing a mapping from input data (normally described by several features) to the appropriate outputs. Within supervised learning, one type of task is a classification learning task, in which each output is one or more classes to which the input belongs. In supervised learning, a set of training examples---examples with known output values---is used by a learning algorithm to generate a model. This model is intended to approximate the mapping between the inputs and outputs. This model can be used to generate predicted outputs for inputs that have not been seen before. For example, we may have data consisting of observations of sunspots. In a classification learning task, our goal may be to learn to classify sunspots into one of several types. Each example may correspond to one candidate sunspot with various measurements or just an image. A learning algorithm would use the supplied examples to generate a model that approximates the mapping between each supplied set of measurements and the type of sunspot. This model can then be used to classify previously unseen sunspots based on the candidate's measurements. This chapter discusses methods to perform machine learning, with examples involving astronomy.

Oza, Nikunj C.

2011-01-01

171

Brain  

MedlinePLUS

... will return after updating. Resources Archived Modules Updates Brain Cerebrum The cerebrum is the part of the ... the outside of the brain and spinal cord. Brain Stem The brain stem is the part of ...

172

Prediction of central nervous system embryonal tumour outcome based on gene expression  

Microsoft Academic Search

Embryonal tumours of the central nervous system (CNS) represent a heterogeneous group of tumours about which little is known biologically, and whose diagnosis, on the basis of morphologic appearance alone, is controversial. Medulloblastomas, for example, are the most common malignant brain tumour of childhood, but their pathogenesis is unknown, their relationship to other embryonal CNS tumours is debated, and patients'

Scott L. Pomeroy; Pablo Tamayo; Michelle Gaasenbeek; Lisa M. Sturla; Michael Angelo; Margaret E. McLaughlin; John Y. H. Kim; Liliana C. Goumnerova; Peter M. Black; Ching Lau; Jeffrey C. Allen; David Zagzag; James M. Olson; Tom Curran; Cynthia Wetmore; Jaclyn A. Biegel; Tomaso Poggio; Shayan Mukherjee; Ryan Rifkin; Andrea Califano; Gustavo Stolovitzky; David N. Louis; Jill P. Mesirov; Eric S. Lander; Todd R. Golub

2002-01-01

173

An Ensemble-of-Classifiers Based Approach for Early Diagnosis of Alzheimer's Disease: Classification Using Structural Features of Brain Images  

PubMed Central

Structural brain imaging is playing a vital role in identification of changes that occur in brain associated with Alzheimer's disease. This paper proposes an automated image processing based approach for the identification of AD from MRI of the brain. The proposed approach is novel in a sense that it has higher specificity/accuracy values despite the use of smaller feature set as compared to existing approaches. Moreover, the proposed approach is capable of identifying AD patients in early stages. The dataset selected consists of 85 age and gender matched individuals from OASIS database. The features selected are volume of GM, WM, and CSF and size of hippocampus. Three different classification models (SVM, MLP, and J48) are used for identification of patients and controls. In addition, an ensemble of classifiers, based on majority voting, is adopted to overcome the error caused by an independent base classifier. Ten-fold cross validation strategy is applied for the evaluation of our scheme. Moreover, to evaluate the performance of proposed approach, individual features and combination of features are fed to individual classifiers and ensemble based classifier. Using size of left hippocampus as feature, the accuracy achieved with ensemble of classifiers is 93.75%, with 100% specificity and 87.5% sensitivity. PMID:25276224

Farhan, Saima; Tauseef, Huma

2014-01-01

174

Aged-related changes in brain activity classification with respect to age by means of graph indexes.  

PubMed

Recent studies have investigated changes in the human brain network organization during the normal aging. A reduction of the connectivity between brain areas was demonstrated by combining neuroimaging technologies and graph theory. Clustering, characteristic path length and small-worldness are key topological measures and they are widely used in literature. In this paper we propose a new methodology that combine advanced techniques of effective connectivity estimation, graph theoretical approach and classification by SVM method. EEG signals recording during rest condition from 20 young subjects and 20 mid-aged adults were studied. Partial Directed Coherence was computed by means of General Linear Kalman Filter and graph indexes were extracted from estimated patterns. At last small-worldness was used as feature for the SVM classifier. Results show that topological differences of brain networks exist between young and mid-aged adults: small-worldness is significantly different between the two populations and it can be used to classify the subjects with respect to age with an accuracy of 69%. PMID:24110696

Petti, M; Toppi, J; Pichiorri, F; Cincotti, F; Salinari, S; Babiloni, F; Astolfi, L; Mattia, D

2013-01-01

175

Partial volume effect modeling for segmentation and tissue classification of brain magnetic resonance images: A review  

PubMed Central

Quantitative analysis of magnetic resonance (MR) brain images are facilitated by the development of automated segmentation algorithms. A single image voxel may contain of several types of tissues due to the finite spatial resolution of the imaging device. This phenomenon, termed partial volume effect (PVE), complicates the segmentation process, and, due to the complexity of human brain anatomy, the PVE is an important factor for accurate brain structure quantification. Partial volume estimation refers to a generalized segmentation task where the amount of each tissue type within each voxel is solved. This review aims to provide a systematic, tutorial-like overview and categorization of methods for partial volume estimation in brain MRI. The review concentrates on the statistically based approaches for partial volume estimation and also explains differences to other, similar image segmentation approaches. PMID:25431640

Tohka, Jussi

2014-01-01

176

Partial volume effect modeling for segmentation and tissue classification of brain magnetic resonance images: A review.  

PubMed

Quantitative analysis of magnetic resonance (MR) brain images are facilitated by the development of automated segmentation algorithms. A single image voxel may contain of several types of tissues due to the finite spatial resolution of the imaging device. This phenomenon, termed partial volume effect (PVE), complicates the segmentation process, and, due to the complexity of human brain anatomy, the PVE is an important factor for accurate brain structure quantification. Partial volume estimation refers to a generalized segmentation task where the amount of each tissue type within each voxel is solved. This review aims to provide a systematic, tutorial-like overview and categorization of methods for partial volume estimation in brain MRI. The review concentrates on the statistically based approaches for partial volume estimation and also explains differences to other, similar image segmentation approaches. PMID:25431640

Tohka, Jussi

2014-11-28

177

Classification of brain compartments and head injury lesions by neural networks applied to magnetic resonance images  

E-print Network

between gray and white matter, but the CSF signal is usually isotense with brain parenchyma [15] . "Adding the early and late echos, (PD+T2), enhances gray matter/white matter contrast [8]. " Additional amplitude features that were explored included... in the feature vector because of the different anatomical levels, brain morphology, and image array registration. Object template matching [13], [14] was not explicitly used in lesion detection due to the vast differences in lesion size and morphology ~ 32...

Kischell, Eric Robert

1993-01-01

178

The impact of image dynamic range on texture classification of brain white matter  

Microsoft Academic Search

BACKGROUND: The Greylevel Cooccurrence Matrix method (COM) is one of the most promising methods used in Texture Analysis of Magnetic Resonance Images. This method provides statistical information about the spatial distribution of greylevels in the image which can be used for classification of different tissue regions. Optimizing the size and complexity of the COM has the potential to enhance the

Doaa Mahmoud-Ghoneim; Mariam K Alkaabi; Jacques D de Certaines; Frank-M Goettsche

2008-01-01

179

3-D MRI Brain Scan Feature Classification Using an Oct-tree Representation  

E-print Network

segmentation, Oct-tree representation, Image classification. 1 Introduction Image mining involves a number that allows the effective application of data mining techniques. The nature of the image representation will affect both the efficiency and effectiveness of the data mining. We can divide the domain of image mining

Coenen, Frans

180

The impact of severe traumatic brain injury on a novel base deficit- based classification of hypovolemic shock  

PubMed Central

Background Recently, our group has proposed a new classification of hypovolemic shock based on the physiological shock marker base deficit (BD). The classification consists of four groups of worsening BD and correlates with the extent of hypovolemic shock in severely injured patients. The aim of this study was to test the applicability of our recently proposed classification of hypovolemic shock in the context of severe traumatic brain injury (TBI). Methods Between 2002 and 2011, patients ?16 years in age with an AIShead???3 have been retrieved from the German TraumaRegister DGU® database. Patients were classified into four strata of worsening BD [(class I (BD???2 mmol/l), class II (BD?>?2.0 to 6.0 mmol/l), class III (BD?>?6.0 to 10 mmol/l) and class IV (BD?>?10 mmol/l)] and assessed for demographic and injury characteristics as well as blood product transfusions and outcomes. The cohort of severely injured patients with TBI was compared to a population of all trauma patients to assess possible differences in the applicability of the BD based classification of hypovolemic shock. Results From a total of 23,496 patients, 10,201 multiply injured patients with TBI (AIShead???3) could be identified. With worsening of BD, a consecutive increase of mortality rate from 15.9% in class I to 61.4% in class IV patients was observed. Simultaneously, injury severity scores increased from 20.8 (±11.9) to 41.6 (±17). Increments in BD paralleled decreasing hemoglobin, platelet counts and Quick’s values. The number of blood units transfused correlated with worsening of BD. Massive transfusion rates increased from 5% in class I to 47% in class IV. Between multiply injured patients with TBI and all trauma patients, no clinically relevant differences in transfusion requirement or massive transfusion rates were observed. Conclusion The presence of TBI has no relevant impact on the applicability of the recently proposed BD-based classification of hypovolemic shock. This study underlines the role of BD as a relevant clinical indicator of hypovolaemic shock during the initial assessment in respect to haemostatic resuscitation and transfusion requirements. PMID:24779431

2014-01-01

181

Peculiarities of hyperlipidaemia in tumour patients.  

PubMed Central

The study group included 684 cases: 258 patients with breast carcinoma, 113 males with lung cancer, 42 patients with rectal tumours, 42 patients with stomach tumours, 59 patients with fibroadenomatosis, and 170 healthy subjects of varying age (male and female). A relatively high blood triglyceride level was found in patients with breast, lung, rectal (females), and stomach (female) tumours. The blood concentration of high-density lipoprotein-cholesterol in patients with breast, lung, and stomach (female) tumours was relatively low. The elimination of tumour (breast carcinoma) did not lead to significant changes in lipid metabolism. There was no correlation between degree of lipidaemia and stage of tumour progression except in the cases of rectal cancer. Preliminary results are presented on the tentative classification of hyperlipoproteinaemia in tumour patients, using the lipid concentration threshold values advocated by Carlson et al. (1977); an increased frequency of Type IV hyperlipoproteinaemia proved to be the most characteristic feature of tumour patients. The results are discussed in terms of the concept of the importance of lipid metabolic disturbances, primarily those due to ageing, in the genesis of the syndrome of "cancerophilia" (predisposition to cancer). PMID:7248149

Dilman, V. M.; Berstein, L. M.; Ostroumova, M. N.; Tsyrlina, Y. V.; Golubev, A. G.

1981-01-01

182

Finding Distinctive Shape Features for Automatic Hematoma Classification in Head CT Images from Traumatic Brain Injuries  

E-print Network

, chengli,leehk}@bii.a-star.edu.sg Bolan Su, Chew Lim Tan School of Computing National University: lis@i2r.a-star.edu.sg C. C. Tchoyoson Lim, Boon Chuan Pang, Cheng Kiang Lee National Neuroscience of traumatic brain injury (TBI) patients with hematomas. Hematoma caused by blood vessel rupture is the major

Tan, Chew Lim

183

WAIS Digit Span-Based Indicators of Malingered Neurocognitive Dysfunction: Classification Accuracy in Traumatic Brain Injury  

ERIC Educational Resources Information Center

The present study determined specificity and sensitivity to malingered neurocognitive dysfunction (MND) in traumatic brain injury (TBI) for several Wechsler Adult Intelligence Scale (WAIS) Digit Span scores. TBI patients (n = 344) were categorized into one of five groups: no incentive, incentive only, suspect, probable MND, and definite MND.…

Heinly, Matthew T.; Greve, Kevin W.; Bianchini, Kevin J.; Love, Jeffrey M.; Brennan, Adrianne

2005-01-01

184

Support vector machine classification and characterization of age-related reorganization of functional brain networks  

PubMed Central

Most of what is known about the reorganization of functional brain networks that accompanies normal aging is based on neuroimaging studies in which participants perform specific tasks. In these studies, reorganization is defined by the differences in task activation between young and old adults. However, task activation differences could be the result of differences in task performance, strategy, or motivation, and not necessarily reflect reorganization. Resting-state fMRI provides a method of investigating functional brain networks without such confounds. Here, a support vector machine (SVM) classifier was used in an attempt to differentiate older adults from younger adults based on their resting-state functional connectivity. In addition, the information used by the SVM was investigated to see what functional connections best differentiated younger adult brains from older adult brains. Three separate resting-state scans from 26 younger adults (18-35 yrs) and 26 older adults (55-85) were obtained from the International Consortium for Brain Mapping (ICBM) dataset made publically available in the 1000 Functional Connectomes project www.nitrc.org/projects/fcon_1000. 100 seed-regions from four functional networks with 5 mm3 radius were defined based on a recent study using machine learning classifiers on adolescent brains. Time-series for every seed-region were averaged and three matrices of z-transformed correlation coefficients were created for each subject corresponding to each individual’s three resting-state scans. SVM was then applied using leave-one-out cross-validation. The SVM classifier was 84% accurate in classifying older and younger adult brains. The majority of the connections used by the classifier to distinguish subjects by age came from seed-regions belonging to the sensorimotor and cingulo-opercular networks. These results suggest that age-related decreases in positive correlations within the cingulo-opercular and default networks, and decreases in negative correlations between the default and sensorimotor networks, are the distinguishing characteristics of age-related reorganization. PMID:22227886

Meier, Timothy B.; Desphande, Alok S.; Vergun, Svyatoslav; Nair, Veena A.; Song, Jie; Biswal, Bharat B.; Meyerand, Mary E.; Birn, Rasmus M.; Prabhakaran, Vivek

2012-01-01

185

A parametric feature extraction and classification strategy for brain-computer interfacing  

Microsoft Academic Search

Parametric modeling strategies are explored in conjunction with linear discriminant analysis for use in an electroencephalogram (EEG)-based brain-computer interface (BCI). A left\\/right self-paced typing exercise is analyzed by extending the usual autoregressive (AR) model for EEG feature extraction with an AR with exogenous input (ARX) model for combined filtering and feature extraction. The ensemble averaged Bereitschaftspotential (an event related potential

Dave P. Burke; Simon P. Kelly; Philip de Chazal; Richard B. Reilly; Ciarán Finucane

2005-01-01

186

Multi-parametric Classification of Traumatic Brain Injury Patients Using Automatic Analysis of Quantitative MRI Scans  

Microsoft Academic Search

\\u000a Traumatic brain injury (TBI) is ranked as the fourth highest cause of death in the developed world. The majority of patients\\u000a sustain mild TBI, and a significant number suffer persistent neuropsychological problems. Conventional neuroimaging methods\\u000a (CT, MRI) do not reveal abnormalities consistent with the cognitive symptoms. Imaging methods offering prognostic information\\u000a in acutely injured patients are therefore required. Here we

Benjamin S. Aribisala; Christopher J. A. Cowie; Jiabao He; Joshua Wood; A. David Mendelow; Patrick Mitchell; Andrew M. Blamire

2010-01-01

187

MR Brain Tissue Classification Using an Edge-Preserving Spatially Variant Bayesian Mixture Model  

Microsoft Academic Search

\\u000a In this paper, a spatially constrained mixture model for the segmentation of MR brain images is presented. The novelty of\\u000a this work is an edge-preserving smoothness prior which is imposed on the probabilities of the voxel labels. This prior incorporates\\u000a a line process, which is modeled as a Bernoulli random variable, in order to preserve edges between tissues. The main

Giorgos Sfikas; Christophoros Nikou; Nikolas P. Galatsanos; Christian Heinrich

2008-01-01

188

Classification of Self-Driven Mental Tasks from Whole-Brain Activity Patterns  

PubMed Central

During wakefulness, a constant and continuous stream of complex stimuli and self-driven thoughts permeate the human mind. Here, eleven participants were asked to count down numbers and remember negative or positive autobiographical episodes of their personal lives, for 32 seconds at a time, during which they could freely engage in the execution of those tasks. We then examined the possibility of determining from a single whole-brain functional magnetic resonance imaging scan which one of the two mental tasks each participant was performing at a given point in time. Linear support-vector machines were used to build within-participant classifiers and across-participants classifiers. The within-participant classifiers could correctly discriminate scans with an average accuracy as high as 82%, when using data from all individual voxels in the brain. These results demonstrate that it is possible to accurately classify self-driven mental tasks from whole-brain activity patterns recorded in a time interval as short as 2 seconds. PMID:24824899

Nawa, Norberto Eiji; Ando, Hiroshi

2014-01-01

189

Randomized pilot study and qualitative evaluation of a clinical decision support system for brain tumour diagnosis based on SV ¹H MRS: evaluation as an additional information procedure for novice radiologists.  

PubMed

The results of a randomized pilot study and qualitative evaluation of the clinical decision support system Curiam BT are reported. We evaluated the system's feasibility and potential value as a radiological information procedure complementary to magnetic resonance (MR) imaging to assist novice radiologists in diagnosing brain tumours using MR spectroscopy (1.5 and 3.0T). Fifty-five cases were analysed at three hospitals according to four non-exclusive diagnostic questions. Our results show that Curiam BT improved the diagnostic accuracy in all the four questions. Additionally, we discuss the findings of the users' feedback about the system, and the further work to optimize it for real environments and to conduct a large clinical trial. PMID:24480160

Sáez, Carlos; Martí-Bonmatí, Luis; Alberich-Bayarri, Angel; Robles, Montserrat; García-Gómez, Juan M

2014-02-01

190

Brain Tumor Classification Using AFM in Combination with Data Mining Techniques  

PubMed Central

Although classification of astrocytic tumors is standardized by the WHO grading system, which is mainly based on microscopy-derived, histomorphological features, there is great interobserver variability. The main causes are thought to be the complexity of morphological details varying from tumor to tumor and from patient to patient, variations in the technical histopathological procedures like staining protocols, and finally the individual experience of the diagnosing pathologist. Thus, to raise astrocytoma grading to a more objective standard, this paper proposes a methodology based on atomic force microscopy (AFM) derived images made from histopathological samples in combination with data mining techniques. By comparing AFM images with corresponding light microscopy images of the same area, the progressive formation of cavities due to cell necrosis was identified as a typical morphological marker for a computer-assisted analysis. Using genetic programming as a tool for feature analysis, a best model was created that achieved 94.74% classification accuracy in distinguishing grade II tumors from grade IV ones. While utilizing modern image analysis techniques, AFM may become an important tool in astrocytic tumor diagnosis. By this way patients suffering from grade II tumors are identified unambiguously, having a less risk for malignant transformation. They would benefit from early adjuvant therapies. PMID:24062997

Huml, Marlene; Silye, René; Zauner, Gerald

2013-01-01

191

Tumour biology: Senescence in premalignant tumours  

NASA Astrophysics Data System (ADS)

Oncogene-induced senescence is a cellular response that may be crucial for protection against cancer development, but its investigation has so far been restricted to cultured cells that have been manipulated to overexpress an oncogene. Here we analyse tumours initiated by an endogenous oncogene, ras, and show that senescent cells exist in premalignant tumours but not in malignant ones. Senescence is therefore a defining feature of premalignant tumours that could prove valuable in the diagnosis and prognosis of cancer.

Collado, Manuel; Gil, Jesús; Efeyan, Alejo; Guerra, Carmen; Schuhmacher, Alberto J.; Barradas, Marta; Benguría, Alberto; Zaballos, Angel; Flores, Juana M.; Barbacid, Mariano; Beach, David; Serrano, Manuel

2005-08-01

192

Congenital primitive neuroectodermal tumour presenting as obstructed labour  

PubMed Central

Brain tumours presenting at delivery are extremely rare. A case of primitive neuroectodermal tumour (PNET) that presented intrapartum with failure to progress due to hydrocephalus is reported. Diagnosis required imaging with magnetic resonance and computed tomography in addition to open biopsy.?? PMID:9713037

Inwald, D.; Kempley, S.; Hird, M.

1998-01-01

193

Congenital primitive neuroectodermal tumour presenting as obstructed labour.  

PubMed

Brain tumours presenting at delivery are extremely rare. A case of primitive neuroectodermal tumour (PNET) that presented intrapartum with failure to progress due to hydrocephalus is reported. Diagnosis required imaging with magnetic resonance and computed tomography in addition to open biopsy. PMID:9713037

Inwald, D; Kempley, S; Hird, M

1998-05-01

194

A Knowledge Discovery Approach to Diagnosing Intracranial Hematomas on Brain CT: Recognition, Measurement and Classification  

NASA Astrophysics Data System (ADS)

Computed tomography (CT) of the brain is preferred study on neurological emergencies. Physicians use CT to diagnose various types of intracranial hematomas, including epidural, subdural and intracerebral hematomas according to their locations and shapes. We propose a novel method that can automatically diagnose intracranial hematomas by combining machine vision and knowledge discovery techniques. The skull on the CT slice is located and the depth of each intracranial pixel is labeled. After normalization of the pixel intensities by their depth, the hyperdense area of intracranial hematoma is segmented with multi-resolution thresholding and region-growing. We then apply C4.5 algorithm to construct a decision tree using the features of the segmented hematoma and the diagnoses made by physicians. The algorithm was evaluated on 48 pathological images treated in a single institute. The two discovered rules closely resemble those used by human experts, and are able to make correct diagnoses in all cases.

Liao, Chun-Chih; Xiao, Furen; Wong, Jau-Min; Chiang, I.-Jen

195

Tumour biology: Senescence in premalignant tumours  

Microsoft Academic Search

Oncogene-induced senescence is a cellular response that may be crucial for protection against cancer development, but its investigation has so far been restricted to cultured cells that have been manipulated to overexpress an oncogene. Here we analyse tumours initiated by an endogenous oncogene, ras, and show that senescent cells exist in premalignant tumours but not in malignant ones. Senescence is

Manuel Collado; Jesús Gil; Alejo Efeyan; Carmen Guerra; Alberto J. Schuhmacher; Marta Barradas; Alberto Benguría; Angel Zaballos; Juana M. Flores; Mariano Barbacid; David Beach; Manuel Serrano

2005-01-01

196

Gender, Race, and Survival: A Study in Non-Small-Cell Lung Cancer Brain Metastases Patients Utilizing the Radiation Therapy Oncology Group Recursive Partitioning Analysis Classification  

SciTech Connect

Purpose: To explore whether gender and race influence survival in non-small-cell lung cancer (NSCLC) in patients with brain metastases, using our large single-institution brain tumor database and the Radiation Therapy Oncology Group recursive partitioning analysis (RPA) brain metastases classification. Methods and materials: A retrospective review of a single-institution brain metastasis database for the interval January 1982 to September 2004 yielded 835 NSCLC patients with brain metastases for analysis. Patient subsets based on combinations of gender, race, and RPA class were then analyzed for survival differences. Results: Median follow-up was 5.4 months (range, 0-122.9 months). There were 485 male patients (M) (58.4%) and 346 female patients (F) (41.6%). Of the 828 evaluable patients (99%), 143 (17%) were black/African American (B) and 685 (83%) were white/Caucasian (W). Median survival time (MST) from time of brain metastasis diagnosis for all patients was 5.8 months. Median survival time by gender (F vs. M) and race (W vs. B) was 6.3 months vs. 5.5 months (p = 0.013) and 6.0 months vs. 5.2 months (p = 0.08), respectively. For patients stratified by RPA class, gender, and race, MST significantly favored BFs over BMs in Class II: 11.2 months vs. 4.6 months (p = 0.021). On multivariable analysis, significant variables were gender (p = 0.041, relative risk [RR] 0.83) and RPA class (p < 0.0001, RR 0.28 for I vs. III; p < 0.0001, RR 0.51 for II vs. III) but not race. Conclusions: Gender significantly influences NSCLC brain metastasis survival. Race trended to significance in overall survival but was not significant on multivariable analysis. Multivariable analysis identified gender and RPA classification as significant variables with respect to survival.

Videtic, Gregory M.M., E-mail: videtig@ccf.or [Department of Radiation Oncology, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH (United States); Reddy, Chandana A. [Department of Radiation Oncology, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH (United States); Chao, Samuel T. [Department of Radiation Oncology, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH (United States); Brain Tumor and NeuroOncology Center, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH (United States); Rice, Thomas W. [Department of Thoracic and Cardiovascular Surgery, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH (United States); Adelstein, David J. [Department of Hematology and Medical Oncology, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH (United States); Barnett, Gene H. [Brain Tumor and NeuroOncology Center, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH (United States); Department of Neurosurgery, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH (United States); Mekhail, Tarek M. [Department of Hematology and Medical Oncology, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH (United States); Vogelbaum, Michael A. [Brain Tumor and NeuroOncology Center, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH (United States); Department of Neurosurgery, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH (United States); Suh, John H. [Department of Radiation Oncology, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH (United States); Brain Tumor and NeuroOncology Center, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH (United States)

2009-11-15

197

Evidence for label-retaining tumour-initiating cells in human glioblastoma  

PubMed Central

Individual tumour cells display diverse functional behaviours in terms of proliferation rate, cell–cell interactions, metastatic potential and sensitivity to therapy. Moreover, sequencing studies have demonstrated surprising levels of genetic diversity between individual patient tumours of the same type. Tumour heterogeneity presents a significant therapeutic challenge as diverse cell types within a tumour can respond differently to therapies, and inter-patient heterogeneity may prevent the development of general treatments for cancer. One strategy that may help overcome tumour heterogeneity is the identification of tumour sub-populations that drive specific disease pathologies for the development of therapies targeting these clinically relevant sub-populations. Here, we have identified a dye-retaining brain tumour population that displays all the hallmarks of a tumour-initiating sub-population. Using a limiting dilution transplantation assay in immunocompromised mice, label-retaining brain tumour cells display elevated tumour-initiation properties relative to the bulk population. Importantly, tumours generated from these label-retaining cells exhibit all the pathological features of the primary disease. Together, these findings confirm dye-retaining brain tumour cells exhibit tumour-initiation ability and are therefore viable targets for the development of therapeutics targeting this sub-population. PMID:21515906

Deleyrolle, Loic P.; Harding, Angus; Cato, Kathleen; Siebzehnrubl, Florian A.; Rahman, Maryam; Azari, Hassan; Olson, Sarah; Gabrielli, Brian; Osborne, Geoffrey; Vescovi, Angelo

2011-01-01

198

Classification of hemodynamic responses associated with force and speed imagery for a brain-computer interface.  

PubMed

Functional near-infrared spectroscopy (fNIRS) is an emerging optical technique, which can assess brain activities associated with tasks. In this study, six participants were asked to perform three imageries of hand clenching associated with force and speed, respectively. Joint mutual information (JMI) criterion was used to extract the optimal features of hemodynamic responses. And extreme learning machine (ELM) was employed to be the classifier. ELM solved the major bottleneck of feedforward neural networks in learning speed, this classifier was easily implemented and less sensitive to specified parameters. The 2-class fNIRS-BCI system was firstly built with an average accuracy of 76.7 %, when all force and speed tasks were categorized as one class, respectively. The multi-class systems based on different levels of force and speed attempted to be investigated, the accuracies were moderate. This study provided a novel paradigm for establishing fNIRS-BCI system, and provided a possibility to produce more degrees of freedom in BCI system. PMID:25732084

Yin, Xuxian; Xu, Baolei; Jiang, Changhao; Fu, Yunfa; Wang, Zhidong; Li, Hongyi; Shi, Gang

2015-05-01

199

[The role of diagnostic neuropathology in familial tumour syndromes].  

PubMed

Inherited cancer syndromes often involve the central and peripheral nervous system. For the surgical neuropathologist the possibility in individual patients of a familial tumour syndrome needs to be considered in the case of special tumours such as malignant peripheral nerve sheath tumour (MPNST), medulloblastoma with extensive nodularity (MBEN) or even atypical teratoid/rhabdoid tumour (AT/RT) of the brain. Furthermore, tumour location and patient age may point to a familial tumour syndrome as in the case of neurofibromatosis type 2 (NF2) with typical bilateral vestibular schwannoma in young age. This short review discusses some of the diagnostic aspects in this field relating to neurofibromatosis type 1 and 2 (NF1, NF2), as well as the two rare tumors MBEN in Gorlin-Goltz syndrome and AT/RT in particular. PMID:20848106

Feiden, S; Sartorius, E; Feiden, W

2010-10-01

200

Imaging of sacral tumours  

Microsoft Academic Search

All components of the sacrum (bone, cartilage, bone marrow, meninges, nerves, notochord remnants, etc.) can give rise to benign\\u000a or malignant tumours. Bone metastases and intraosseous sites of haematological malignancies, lymphoma and multiple myeloma\\u000a are the most frequent aetiologies, while primary bone tumours and meningeal or nerve tumours are less common. Some histological\\u000a types have a predilection for the sacrum,

S. Gerber; L. Ollivier; J. Leclère; D. Vanel; G. Missenard; H. Brisse; G. de Pinieux; S. Neuenschwander

2008-01-01

201

Endoscopic Ultrasonography of Neuroendocrine Tumours  

Microsoft Academic Search

Neuroendocrine tumours (NETs) of the upper gastrointestinal tract are mainly located in the pancreas, stomach or duodenum. The aims of preoperative work-up are the localization of primary tumour(s), determination of local tumour invasion, of lymph node metastases and of the hormones secreted by the tumour. Endoscopic ultrasonography (EUS) offers ideal conditions to localize and stage NETs of the foregut. We

T. Zimmer; H. Scherübl; S. Faiss; U. Stölzel; E.-O. Riecken; B. Wiedenmann

2000-01-01

202

DNA repair protein O6-alkylguanine-DNA alkyltransferase is phosphorylated by two distinct and novel protein kinases in human brain tumour cells.  

PubMed Central

We showed recently that human O(6)-alkylguanine-DNA alkyltransferase (AGT), an important target for improving cancer chemotherapy, is a phosphoprotein and that phosphorylation inhibits its activity [Srivenugopal, Mullapudi, Shou, Hazra and Ali-Osman (2000) Cancer Res. 60, 282-287]. In the present study we characterized the cellular kinases that phosphorylate AGT in the human medulloblastoma cell line HBT228. Crude cell extracts used Mg(2+) more efficiently than Mn(2+) for phosphorylating human recombinant AGT (rAGT) protein. Both [gamma-(32)P]ATP and [gamma-(32)P]GTP served as phosphate donors, with the former being twice as efficient. Specific components known to activate protein kinase A, protein kinase C and calmodulin-dependent kinases did not stimulate the phosphorylation of rAGT. Phosphoaminoacid analysis after reaction in vitro with ATP or GTP showed that AGT was modified at the same amino acids (serine, threonine and tyrosine) as in intact HBT228 cells. Although some of these properties pointed to casein kinase II as a candidate enzyme, known inhibitors and activators of casein kinase II did not affect rAGT phosphorylation. Fractionation of the cell extracts on poly(Glu/Tyr)-Sepharose resulted in the adsorption of an AGT kinase that modified the tyrosine residues and the exclusion of a fraction that phosphorylated AGT on serine and threonine residues. In-gel kinase assays after SDS/PAGE and non-denaturing PAGE revealed the presence of two AGT kinases of 75 and 130 kDa in HBT228 cells. The partly purified tyrosine kinase, identified as the 130 kDa enzyme by the same assays, was strongly inhibited by tyrphostin 25 but not by genestein. The tyrosine kinase used ATP or GTP to phosphorylate the AGT protein; this reaction inhibited the DNA repair activity of AGT. Evidence that the kinases might physically associate with AGT in cells was also provided. These results demonstrate that two novel cellular protein kinases, a tyrosine kinase and a serine/threonine kinase, both capable of using GTP as a donor, phosphorylate the AGT protein and affect its function. The new kinases might serve as potential targets for strengthening the biochemical modulation of AGT in human tumours. PMID:11023825

Mullapudi, S R; Ali-Osman, F; Shou, J; Srivenugopal, K S

2000-01-01

203

Brain metastases.  

PubMed

Brain metastases are the most frequent neurological complication of cancer and the most common brain tumour type. Lung and breast cancers, and melanoma are responsible for up to three-quarters of metastatic brain lesions. Most patients exhibit either headache, seizures, focal deficits, cognitive or gait disorders, which severely impair the quality of life. Brain metastases are best demonstrated by MRI, which is sensitive but non-specific. The main differential diagnosis includes primary tumours, abscesses, vascular and inflammatory lesions. Overall prognosis is poor and depends on age, extent and activity of the systemic disease, number of brain metastases and performance status. In about half of the patients, especially those with widespread and uncontrolled systemic malignancy, death is heavily related to extra-neural lesions, and treatment of cerebral disease doesn't significantly improve survival. In such patients the aim is to improve or stabilize the neurological deficit and maintain quality of life. Corticosteroids and whole-brain radiotherapy usually fulfill this purpose. By contrast, patients with limited number of brain metastases, good performance status and controlled or limited systemic disease, may benefit from aggressive treatment as both quality of life and survival are primarily related to treatment of brain lesions. Several efficacious therapeutic options including surgery, radiotherapy and chemotherapy are available for these patients. PMID:24365409

Gállego Pérez-Larraya, Jaime; Hildebrand, Jerzy

2014-01-01

204

Investigating the Use of Support Vector Machine Classification on Structural Brain Images of Preterm–Born Teenagers as a Biological Marker  

PubMed Central

Preterm birth has been shown to induce an altered developmental trajectory of brain structure and function. With the aid support vector machine (SVM) classification methods we aimed to investigate whether MRI data, collected in adolescence, could be used to predict whether an individual had been born preterm or at term. To this end we collected T1–weighted anatomical MRI data from 143 individuals (69 controls, mean age 14.6y). The inclusion criteria for those born preterm were birth weight ? 1500g and gestational age < 37w. A linear SVM was trained on the grey matter segment of MR images in two different ways. First, all the individuals were used for training and classification was performed by the leave–one–out method, yielding 93% correct classification (sensitivity = 0.905, specificity = 0.942). Separately, a random half of the available data were used for training twice and each time the other, unseen, half of the data was classified, resulting 86% and 91% accurate classifications. Both gestational age (R = –0.24, p<0.04) and birth weight (R = –0.51, p < 0.001) correlated with the distance to decision boundary within the group of individuals born preterm. Statistically significant correlations were also found between IQ (R = –0.30, p < 0.001) and the distance to decision boundary. Those born small for gestational age did not form a separate subgroup in these analyses. The high rate of correct classification by the SVM motivates further investigation. The long–term goal is to automatically and non–invasively predict the outcome of preterm–born individuals on an individual basis using as early a scan as possible. PMID:25837791

Chu, Carlton; Lagercrantz, Hugo; Forssberg, Hans; Nagy, Zoltan

2015-01-01

205

Proton MR spectroscopy of cerebral gliomas at 3 T: spatial heterogeneity, and tumour grade and extent.  

PubMed

This study aimed to evaluate the usefulness of proton MR spectroscopic imaging ((1)H-MRSI) at 3 T in differentiating high- from low-grade gliomas, and tumour from necrosis, oedema or normal tissue. Forty-four patients with brain gliomas and four with meningiomas were retrospectively reviewed. The normalised metabolites choline (nCho), N-acetylaspartate (nNAA), creatine (nCr) and lactate/lipids (nLL), and the metabolite ratios Cho/NAA, NAA/Cr and Cho/Cr were calculated. Necrotic-appearing areas showed two spectroscopic patterns: "necrosis" with variable nCho and high nLL, and "cystic necrosis" with variable nLL or nonevident peaks. Peri-enhancing oedematous-appearing areas showed three spectroscopic patterns ("tumour" with abnormal Cho/NAA, "oedema" with normal Cho/NAA and "tumour/oedema" with normal nCho and abnormal Cho/NAA) in gliomas, and one ("oedema") in meningiomas. Peri-enhancing or peri-tumour normal-appearing areas showed two patterns ("infiltrated" with abnormal nCho and/or Cho/NAA and "normal" with normal spectra) in gliomas and one ("normal") in meningiomas. Discriminant analysis showed that classification accuracy between high- and low-grade glioma masses was better with normalised metabolites or all parameters together than metabolite ratios and that among peri-enhancing areas was much better with normalised metabolites. The analysis of spatial distribution of normalised metabolites by 3-T (1)H-MRSI helps to discriminate among different tissues, offering information not available with conventional MRI. PMID:18389246

Di Costanzo, Alfonso; Scarabino, Tommaso; Trojsi, Francesca; Popolizio, Teresa; Catapano, Domenico; Giannatempo, Giuseppe M; Bonavita, Simona; Portaluri, Maurizio; Tosetti, Michela; d'Angelo, Vincenzo A; Salvolini, Ugo; Tedeschi, Gioacchino

2008-08-01

206

Small Intestinal Tumours  

PubMed Central

Objective. Balloon enteroscopy (BE) and capsule enteroscopy (CE) are enteroscopy methods that allow examination and treatment of the small bowel. Before the CE and BE era, the small intestine was difficult to access for investigation. Small intestinal tumours are infrequent conditions, but about half of them are malignant. Materials and Methods. A total of 303 BEs were performed in 179 patients. Oral insertion was performed in 240 and anal in 63 BEs. Indications for the procedure in our patients with small bowel tumours were anaemia and/or bleeding, obstruction, suspicion of carcinoid tumour, or suspicion of Peutz-Jeghers syndrome. Results. In 50 of our 179 patients (28%), we diagnosed some small intestinal tumours: hamartomas in Peutz-Jeghers syndrome in 16 patients, adenocarcinoma in 7, lymphoma in 6, carcinoid tumour in 4, melanoma and stromal tumour in 3, adenoma, lipoma, and inflammatory polyps in 2, and granular cell tumour, cavernous lymphangioma, fibrolipoma, Cronkhite-Canada polyps, and metastatic involvement in individual cases. Conclusion. BE facilitates exploration and treatment of the small intestine. The procedure is generally safe and useful. BE and CE are essential modalities for the management of small intestinal diseases. PMID:24348540

Kopá?ová, Marcela; Bureš, Jan; Tachecí, Ilja

2013-01-01

207

DICER1 hotspot mutations in non-epithelial gonadal tumours  

PubMed Central

Background: Non-epithelial gonadal tumours largely comprise sex cord-stromal tumours (SCSTs) and germ cell tumours (GCTs). Specific somatic mutations in DICER1, a microRNA maturation pathway gene, have been identified in these tumours. We conducted a study that aimed to confirm, refine and extend the previous observations. Methods: We used Sanger sequencing to sequence the RNase IIIa and IIIb domains of DICER1 in 154 gonadal tumours from 135 females and 19 males, as well as 43 extra-gonadal GCTs from 26 females and 17 males. Results: We identified heterozygous non-synonymous mutations in the RNase IIIb domain of DICER1 in 14/197 non-epithelial tumours (7.1%). Mutations were found in 9/28 SCSTs (32%), 5/118 gonadal GCTs (4.2%), 0/43 extra-gonadal GCTs and 0/8 miscellaneous tumours. The 14 mutations affected only five residues: E1705, D1709, E1788, D1810 and E1813. In all five patients where matched and constitutional DNA was available, the mutations were only somatic. There were no mutations found in the RNase IIIa domain. Conclusion: More than half (8/15) of Sertoli–Leydig cell tumours (SLCTs) harbour DICER1 mutations in the RNase IIIb domain, while mutations are rarely found in GCTs. Genetic alterations in SLCTs may aid in classification and provide new approaches to therapy. PMID:24136150

Witkowski, L; Mattina, J; Schönberger, S; Murray, M J; Huntsman, D G; Reis-Filho, J S; McCluggage, W G; Nicholson, J C; Coleman, N; Calaminus, G; Schneider, D T; Arseneau, J; Stewart, C J R; Foulkes, W D

2013-01-01

208

Classification of a frameshift/extended and a stop mutation in WT1 as gain-of-function mutations that activate cell cycle genes and promote Wilms tumour cell proliferation  

PubMed Central

The WT1 gene encodes a zinc finger transcription factor important for normal kidney development. WT1 is a suppressor for Wilms tumour development and an oncogene for diverse malignant tumours. We recently established cell lines from primary Wilms tumours with different WT1 mutations. To investigate the function of mutant WT1 proteins, we performed WT1 knockdown experiments in cell lines with a frameshift/extension (p.V432fsX87 = Wilms3) and a stop mutation (p.P362X = Wilms2) of WT1, followed by genome-wide gene expression analysis. We also expressed wild-type and mutant WT1 proteins in human mesenchymal stem cells and established gene expression profiles. A detailed analysis of gene expression data enabled us to classify the WT1 mutations as gain-of-function mutations. The mutant WT1Wilms2 and WT1Wilms3 proteins acquired an ability to modulate the expression of a highly significant number of genes from the G2/M phase of the cell cycle, and WT1 knockdown experiments showed that they are required for Wilms tumour cell proliferation. p53 negatively regulates the activity of a large number of these genes that are also part of a core proliferation cluster in diverse human cancers. Our data strongly suggest that mutant WT1 proteins facilitate expression of these cell cycle genes by antagonizing transcriptional repression mediated by p53. We show that mutant WT1 can physically interact with p53. Together the findings show for the first time that mutant WT1 proteins have a gain-of-function and act as oncogenes for Wilms tumour development by regulating Wilms tumour cell proliferation. PMID:24619359

Busch, Maike; Schwindt, Heinrich; Brandt, Artur; Beier, Manfred; Görldt, Nicole; Romaniuk, Paul; Toska, Eneda; Roberts, Stefan; Royer, Hans-Dieter; Royer-Pokora, Brigitte

2014-01-01

209

[Rythmic-pathology: the French national pathology network for thymic epithelial tumours].  

PubMed

Epithelial thymic tumours are rare and sometimes difficult to classify. Since 2010, the French National Cancer Institute supports a French national network, called Rythmic, devoted to the treatment of these tumours through regional and national multidisciplinary conferences using the web. All the tumours are secondarily reviewed by a French pathology national network for classification and staging. This review focuses on the presentation of the Rythmic network, and mainly to the Pathology review process. PMID:24630641

Chalabreysse, Lara; Thomas De Montpreville, Vincent; De Muret, Anne; Hofman, Véronique; Lantuejoul, Sylvie; Parrens, Marie; Payan, Marie-José; Rouquette, Isabelle; Secq, Véronique; Girard, Nicolas; Marx, Alexander; Besse, Benjamin; Molina, Thierry Jo

2014-02-01

210

Recruitment feasibility to a cohort study of endocrine and metabolic health among survivors of childhood brain tumours: a report from the Canadian study of Determinants of Endometabolic Health in ChIlDrEn (CanDECIDE)  

PubMed Central

Objectives The aim of this study was to test the feasibility of recruitment and performance of study procedures of the Canadian Study of Determinants of Endometabolic Health in ChIlDrEn (CanDECIDE) study, which was designed to assess the determinants of endocrine and metabolic health in survivors of childhood brain tumours. Setting A single paediatric tertiary care centre in Hamilton, Ontario, Canada. Participants We included boys and girls, aged 5?years and older, who were lean (body mass index (BMI) below 85th centile for age and gender) or overweight/obese (BMI 85th centile or above for age and gender). We excluded children on steroids or immunosuppressant therapy, smokers and those who had an active infection for the 2?weeks prior to participation. Outcomes Feasibility targets included recruitment rate of at least 50%, the consenting of 80% of participants to provide biological samples, 90% questionnaire completion rate and the ability to process biological samples from at least 80% of participants. Results We approached 210 potential participants, and of the 112 (53%) who agreed to participate, 30 (26.8%) completed the study visit over 7?months. All participants agreed to fast, provide biological samples and complete the questionnaires. Sample collection was successful in 97% (29/30) of participants and laboratory procedures were feasible in 100% of collected samples. We also tested resources required for the conduct of the full study including personnel, space, laboratory equipment and procedures and determined that they are all feasible. Conclusions Recruitment and consenting of patients for the CanDECIDE study may be feasible. However, we are considering prolonging recruitment duration and collaboration with other centres to meet recruitment targets due to lower than expected recruitment rate. Completion of questionnaires and implementation of sample processing protocols are feasible. PMID:24969784

Samaan, M Constantine; Scheinemann, Katrin; Burrow, Sarah; Dillenburg, Rejane F; Barr, Ronald D; Wang, Kuan-Wen; Valencia, Marlie; Thabane, Lehana

2014-01-01

211

Predicting tumour response  

PubMed Central

Abstract Response prediction is an important emerging concept in oncologic imaging, with tailored, individualized treatment regimens increasingly becoming the standard of care. This review aims to define tumour response and illustrate the ways in which imaging techniques can demonstrate tumour biological characteristics that provide information on the likely benefit to be received by treatment. Two imaging approaches are described: identification of therapeutic targets and depiction of the treatment-resistant phenotype. The former approach is exemplified by the use of radionuclide imaging to confirm target expression before radionuclide therapy but with angiogenesis imaging and imaging correlates for genetic response predictors also demonstrating potential utility. Techniques to assess the treatment-resistant phenotype include demonstration of hypoperfusion with dynamic contrast-enhanced computed tomography and magnetic resonance imaging (MRI), depiction of necrosis with diffusion-weighted MRI, imaging of hypoxia and tumour adaption to hypoxia, and 99mTc-MIBI imaging of P-glycoprotein mediated drug resistance. To date, introduction of these techniques into clinical practice has often been constrained by inadequate cross-validation of predictive criteria and lack of verification against appropriate response end points such as survival. With further refinement, imaging predictors of response could play an important role in oncology, contributing to individualization of therapy based on the specific tumour phenotype. This ability to predict tumour response will have implications for improving efficacy of treatment, cost-effectiveness and omission of futile therapy. PMID:24061161

Law, W. Phillip; Miles, Kenneth A.

2013-01-01

212

Tumours of the ovary  

PubMed Central

Ovarian tumours are common in animals, the majority occurring in bitches and cows. The two most important germ cell tumours were dysgerminoma and teratoma; these morphologically resemble their counterparts in women, with the exception that teratomas in animals tend less to malignancy. The granulosa cell tumour is the most frequent sex cord-stromal tumour in all six species and it may contain luteinized areas or show differentiation towards a Sertoli cell pattern. The canine papillary adenoma and papillary adenocarcinoma, which are as common as granulosa tumours, have several features in common with their counterparts in women: they are of similar histological appearance, are frequently bilateral, and the adenocarcinomas have a great propensity for peritoneal implantation metastasis. Ovarian cysts are frequent in the bitch, sow, and cow and may originate from five different anatomical structures in the ovary. ImagesFig. 1Fig. 2 and 3Fig. 20-22Fig. 8-10Fig. 15 and 16Fig. 23Fig. 24Fig. 25Fig. 26Fig. 17-19Fig. 4 and 5Fig. 6 and 7Fig. 11Fig. 12Fig. 13 and 14 PMID:1086151

Nielsen, Svend W.; Misdorp, W.; McEntee, Kenneth

1976-01-01

213

USING MULTIRESOLUTION SPACE-TIME-FREQUENCY FEATURES FOR THE CLASSIFICATION MOTOR IMAGERY EEG RECORDINGS IN A BRAIN COMPUTER  

E-print Network

-frequency segmentation of the given multichannel brain activity recordings to extract subject specific ERD and ERS hemisphere preponderant event related synchronization (ERS) and desynchronization (ERD) [1]. The ERD and ERS neuroscience studies have shown that the ERD and ERS alpha (7-13Hz) and beta (14-32Hz) bands caused by the MI

Minnesota, University of

214

Immunology of naturally transmissible tumours  

PubMed Central

Naturally transmissible tumours can emerge when a tumour cell gains the ability to pass as an infectious allograft between individuals. The ability of these tumours to colonize a new host and to cross histocompatibility barriers contradicts our understanding of the vertebrate immune response to allografts. Two naturally occurring contagious cancers are currently active in the animal kingdom, canine transmissible venereal tumour (CTVT), which spreads among dogs, and devil facial tumour disease (DFTD), among Tasmanian devils. CTVT are generally not fatal as a tumour-specific host immune response controls or clears the tumours after transmission and a period of growth. In contrast, the growth of DFTD tumours is not controlled by the Tasmanian devil's immune system and the disease causes close to 100% mortality, severely impacting the devil population. To avoid the immune response of the host both DFTD and CTVT use a variety of immune escape strategies that have similarities to many single organism tumours, including MHC loss and the expression of immunosuppressive cytokines. However, both tumours appear to have a complex interaction with the immune system of their respective host, which has evolved over the relatively long life of these tumours. The Tasmanian devil is struggling to survive with the burden of this disease and it is only with an understanding of how DFTD passes between individuals that a vaccine might be developed. Further, an understanding of how these tumours achieve natural transmissibility should provide insights into general mechanisms of immune escape that emerge during tumour evolution. PMID:25187312

Siddle, Hannah V; Kaufman, Jim

2015-01-01

215

Immunology of naturally transmissible tumours.  

PubMed

Naturally transmissible tumours can emerge when a tumour cell gains the ability to pass as an infectious allograft between individuals. The ability of these tumours to colonize a new host and to cross histocompatibility barriers contradicts our understanding of the vertebrate immune response to allografts. Two naturally occurring contagious cancers are currently active in the animal kingdom, canine transmissible venereal tumour (CTVT), which spreads among dogs, and devil facial tumour disease (DFTD), among Tasmanian devils. CTVT are generally not fatal as a tumour-specific host immune response controls or clears the tumours after transmission and a period of growth. In contrast, the growth of DFTD tumours is not controlled by the Tasmanian devil's immune system and the disease causes close to 100% mortality, severely impacting the devil population. To avoid the immune response of the host both DFTD and CTVT use a variety of immune escape strategies that have similarities to many single organism tumours, including MHC loss and the expression of immunosuppressive cytokines. However, both tumours appear to have a complex interaction with the immune system of their respective host, which has evolved over the relatively long life of these tumours. The Tasmanian devil is struggling to survive with the burden of this disease and it is only with an understanding of how DFTD passes between individuals that a vaccine might be developed. Further, an understanding of how these tumours achieve natural transmissibility should provide insights into general mechanisms of immune escape that emerge during tumour evolution. PMID:25187312

Siddle, Hannah V; Kaufman, Jim

2015-01-01

216

Diverse effects of hypothermia therapy in patients with severe traumatic brain injury based on the computed tomography classification of the traumatic coma data bank.  

PubMed

A multicenter randomized controlled trial of patients with severe traumatic brain injury who received therapeutic hypothermia or fever control was performed from 2002 to 2008 in Japan (BHYPO). There was no difference in the therapeutic effect on traumatic brain injury between the two groups. The efficacy of hypothermia treatment and the objective of the treatment were reexamined based on a secondary analysis of the BHYPO trial in 135 patients (88 treated with therapeutic hypothermia and 47 with fever control). This analysis was performed to examine clinical outcomes according to the CT classification of the Traumatic Coma Data Bank on admission. Clinical outcomes were evaluated with the Glasgow Outcome Scale and mortality at 6 months after injury. Good recovery and moderate disability were defined as favorable outcomes. Favorable outcomes in young patients (?50 years old) with evacuated mass lesions significantly increased from 33.3% with fever control to 77.8% with therapeutic hypothermia. Patients with diffuse injury III who were treated with therapeutic hypothermia, however, had significantly higher mortality than patients treated with fever control. It was difficult to control intracranial pressure with hypothermia for patients with diffuse injury III, but hypothermia was effective for young patients with an evacuated mass lesion. PMID:25233298

Suehiro, Eiichi; Koizumi, Hiroyasu; Fujisawa, Hirosuke; Fujita, Motoki; Kaneko, Tadashi; Oda, Yasutaka; Yamashita, Susumu; Tsuruta, Ryosuke; Maekawa, Tsuyoshi; Suzuki, Michiyasu

2015-03-01

217

Radiotherapy for ocular tumours.  

PubMed

Ocular tumours present a therapeutic challenge because of the sensitive tissues involved and the necessity to destroy the tumour while minimising visual loss. Radiotherapy (RT) is one of several modalites used apart from surgery, laser, cryotherapy, and chemotherapy. Both external beam RT (EBRT) and brachytherapy are used. Tumours of the bulbar conjunctiva, squamous carcinoma and malignant melanoma, can be treated with a radioactive plaque: strontium-90, ruthenium-106 (Ru-106), or iodine-125 (I-125), after excision. If the tumour involves the fornix or tarsal conjunctiva, proton therapy can treat the conjunctiva and spare most of the eye. Alternatively, an I-125 interstitial implant can be used with shielding of the cornea and lens. Conjunctival mucosal-associated lymphoid tissue lymphoma can be treated with an anterior electron field with lens shielding and 25-30 Gray (Gy) in 2?Gy fractions. Discrete retinoblastoma (RB), too large for cryotherapy or thermolaser, or recurrent after these modalities, can be treated with plaque therapy, I-125, or Ru-106. For large RB, multiple tumours, or vitreous seeds the whole eye can be treated with an I-125 applicator, sparing the bony orbit, or with EBRT, under anaesthetic, using X-rays or proton therapy with vacuum contact lenses to fix the eyes in the required position. Post-enucleated orbits at risk for recurrent RB can be treated with an I-125 implant with shielding to reduce the dose to the bony orbit. Uveal malignant melanomas can be treated with plaque or proton therapy with excellent local control. Preservation of vision will depend on the initial size and location of the tumour. PMID:23174750

Stannard, C; Sauerwein, W; Maree, G; Lecuona, K

2013-02-01

218

Radiotherapy for ocular tumours  

PubMed Central

Ocular tumours present a therapeutic challenge because of the sensitive tissues involved and the necessity to destroy the tumour while minimising visual loss. Radiotherapy (RT) is one of several modalites used apart from surgery, laser, cryotherapy, and chemotherapy. Both external beam RT (EBRT) and brachytherapy are used. Tumours of the bulbar conjunctiva, squamous carcinoma and malignant melanoma, can be treated with a radioactive plaque: strontium-90, ruthenium-106 (Ru-106), or iodine-125 (I-125), after excision. If the tumour involves the fornix or tarsal conjunctiva, proton therapy can treat the conjunctiva and spare most of the eye. Alternatively, an I-125 interstitial implant can be used with shielding of the cornea and lens. Conjunctival mucosal-associated lymphoid tissue lymphoma can be treated with an anterior electron field with lens shielding and 25–30 Gray (Gy) in 2?Gy fractions. Discrete retinoblastoma (RB), too large for cryotherapy or thermolaser, or recurrent after these modalities, can be treated with plaque therapy, I-125, or Ru-106. For large RB, multiple tumours, or vitreous seeds the whole eye can be treated with an I-125 applicator, sparing the bony orbit, or with EBRT, under anaesthetic, using X-rays or proton therapy with vacuum contact lenses to fix the eyes in the required position. Post-enucleated orbits at risk for recurrent RB can be treated with an I-125 implant with shielding to reduce the dose to the bony orbit. Uveal malignant melanomas can be treated with plaque or proton therapy with excellent local control. Preservation of vision will depend on the initial size and location of the tumour. PMID:23174750

Stannard, C; Sauerwein, W; Maree, G; Lecuona, K

2013-01-01

219

Descriptive epidemiology of ependymal tumours in the United States  

PubMed Central

Background: Ependymomas are rare primary gliomas that commonly affect both children and adults, but unique as survival is worse in children. Methods: Data on brain and central nervous system primary malignant and non-malignant ependymal tumours from the Central Brain Tumor Registry of the United States analytic data set and primary malignant ependymal tumours from the SEER 13 registries research data file were used to evaluate incidence and survival, respectively. Results: The 2004–2009 average annual age-adjusted incidence rate of ependymal tumours was 0.41/100?000. Spinal cord/cauda equina was the primary site at diagnosis for 50–60% of ependymal tumours in adult age groups in contrast to about 20% in children and adolescents. Ependymoma was the most frequent histology in all age groups; however, anaplastic ependymoma comprised about 30% in cases 0–19 years of age compared with about 3–5% in adult age groups. Overall, relative survival was favourable with rates at ?85% and 75% at 3 and 10 years post diagnosis, respectively. However, children and adolescents, the oldest adult age group, cases diagnosed with anaplastic ependymoma and/or tumour location in a brain site had lowest survival rates. Conclusion: Paediatric cases had worse outcomes compared with adults for numerous reasons including having a higher percentage of anaplastic ependymomas and greater percentage of cases of intracranial disease. PMID:23660944

Villano, J L; Parker, C K; Dolecek, T A

2013-01-01

220

Radiosensitization of tumours by porphyrins  

Microsoft Academic Search

Our previous data indicate, that hematoporphyrin dimethyl ether (HPde) can totally inhibit the growth of aggressive Ehrlich ascite tumour, when combined with low doses (2Gy) of ionizing radiation. Taking into account these findings, it appears of particular interest to evaluate the dependence of radiosensitizing efficiency of porphyrins on tumour aggressiveness. For this purpose two experimental tumour models (aggressive murine Ehrlich

Zivile Luksiene; Petras Juzenas; Johan Moan

2006-01-01

221

Application of reliability-based automatic repeat request to multi-class classification for brain-computer interfaces  

Microsoft Academic Search

A brain-computer interface (BCI) is a system which could enable patients like those with amyotrophic lateral sclerosis to control some equipment and to communicate with other people, and has been anticipated to be achieved. One of the problems in BCI research is a trade-off between transmission speed and accuracy. In the field of data transmission, on the other hand, reliability-based

Hiromu Takahashi; Tomohiro Yoshikawa; Takeshi Furuhashi

2009-01-01

222

Use of permeability surface area-product to differentiate intracranial tumours from abscess  

PubMed Central

Background and Purpose Clinical and radiological findings of intracranial abscesses may mimic the findings of brain tumours and vice versa. However, the discrimination is of great clinical importance in planning treatment and in following prognosis and response to therapy. This study evaluates the Computed Tomography (CT) perfusion parameters, especially the permeability index, with the aim of evaluating the usefulness of dynamic CT perfusion imaging as an alternative tool to differentiate necrotic brain tumours and intracerebral abscesses. Materials and Methods A total of 21 patients underwent perfusion CT study and were divided into 2 groups: Group 1, patients with necrotic brain tumours (n=13); and Group 2, patients with cerebral abscesses (n=8). The mean perfusion parameters were obtained from the enhancing part of the lesion. The relative ratios were then calculated by using the results from mirrored regions within the contralateral hemisphere as reference. Results The results of this study showed that there was significant difference in the relative permeability surface values between necrotic brain tumours and cerebral abscesses (p=0.005). By applying the ROC curve, a value of 25.1 for rPS was found to be the best estimate to distinguish necrotic brain tumours from cerebral abscesses with a specificity of 88 % and sensitivity of 70 %. Conclusion CT perfusion, especially permeability surface, may allow for better differentiation of cerebral abscesses from brain tumours, making it a strong additional imaging modality in the early diagnosis of these two entities. PMID:21611026

Ramli, N; Rahmat, K; Mah, E; Waran, V; Tan, LK; Chong, HT

2009-01-01

223

Peripheral primitive neuroectodermal tumour and extra-osseous Ewing's sarcoma; a histological, immunohistochemical and DNA flow cytometric study  

Microsoft Academic Search

Although peripheral primitive neuroectodermal tumour (pPNET) and extra-osseous Ewing's sarcoma (EES) are thought to be closely related neoplasms, their clinical behaviour differs considerably. To determine the clinical relevance of the Schmidt classification scheme for differentiating pPNET and EES, 20 tumour specimens of poorly differentiated round cell tumours were evaluated. In addition, the diagnostic value of several neural markers and the

M. Brinkhuis; L. C. D. Wijnaendts; J. C. Linden; J. P. A. Baak; C. J. L. M. Meijer; A. J. M. Unnik; P. A. Voûte

1995-01-01

224

Electrode replacement does not affect classification accuracy in dual-session use of a passive brain-computer interface for assessing cognitive workload  

PubMed Central

The passive brain-computer interface (pBCI) framework has been shown to be a very promising construct for assessing cognitive and affective state in both individuals and teams. There is a growing body of work that focuses on solving the challenges of transitioning pBCI systems from the research laboratory environment to practical, everyday use. An interesting issue is what impact methodological variability may have on the ability to reliably identify (neuro)physiological patterns that are useful for state assessment. This work aimed at quantifying the effects of methodological variability in a pBCI design for detecting changes in cognitive workload. Specific focus was directed toward the effects of replacing electrodes over dual sessions (thus inducing changes in placement, electromechanical properties, and/or impedance between the electrode and skin surface) on the accuracy of several machine learning approaches in a binary classification problem. In investigating these methodological variables, it was determined that the removal and replacement of the electrode suite between sessions does not impact the accuracy of a number of learning approaches when trained on one session and tested on a second. This finding was confirmed by comparing to a control group for which the electrode suite was not replaced between sessions. This result suggests that sensors (both neurological and peripheral) may be removed and replaced over the course of many interactions with a pBCI system without affecting its performance. Future work on multi-session and multi-day pBCI system use should seek to replicate this (lack of) effect between sessions in other tasks, temporal time courses, and data analytic approaches while also focusing on non-stationarity and variable classification performance due to intrinsic factors. PMID:25805963

Estepp, Justin R.; Christensen, James C.

2015-01-01

225

Electrode replacement does not affect classification accuracy in dual-session use of a passive brain-computer interface for assessing cognitive workload.  

PubMed

The passive brain-computer interface (pBCI) framework has been shown to be a very promising construct for assessing cognitive and affective state in both individuals and teams. There is a growing body of work that focuses on solving the challenges of transitioning pBCI systems from the research laboratory environment to practical, everyday use. An interesting issue is what impact methodological variability may have on the ability to reliably identify (neuro)physiological patterns that are useful for state assessment. This work aimed at quantifying the effects of methodological variability in a pBCI design for detecting changes in cognitive workload. Specific focus was directed toward the effects of replacing electrodes over dual sessions (thus inducing changes in placement, electromechanical properties, and/or impedance between the electrode and skin surface) on the accuracy of several machine learning approaches in a binary classification problem. In investigating these methodological variables, it was determined that the removal and replacement of the electrode suite between sessions does not impact the accuracy of a number of learning approaches when trained on one session and tested on a second. This finding was confirmed by comparing to a control group for which the electrode suite was not replaced between sessions. This result suggests that sensors (both neurological and peripheral) may be removed and replaced over the course of many interactions with a pBCI system without affecting its performance. Future work on multi-session and multi-day pBCI system use should seek to replicate this (lack of) effect between sessions in other tasks, temporal time courses, and data analytic approaches while also focusing on non-stationarity and variable classification performance due to intrinsic factors. PMID:25805963

Estepp, Justin R; Christensen, James C

2015-01-01

226

Identification of genes involved in the biology of atypical teratoid/rhabdoid tumours using Drosophila melanogaster  

NASA Astrophysics Data System (ADS)

Atypical teratoid/rhabdoid tumours (AT/RT) are malignant brain tumours. Unlike most other human brain tumours, AT/RT are characterized by inactivation of one single gene, SMARCB1. SMARCB1 is a member of the evolutionarily conserved SWI/SNF chromatin remodelling complex, which has an important role in the control of cell differentiation and proliferation. Little is known, however, about the pathways involved in the oncogenic effects of SMARCB1 inactivation, which might also represent targets for treatment. Here we report a comprehensive genetic screen in the fruit fly that revealed several genes not yet associated with loss of snr1, the Drosophila homologue of SMARCB1. We confirm the functional role of identified genes (including merlin, kibra and expanded, known to regulate hippo signalling pathway activity) in human rhabdoid tumour cell lines and AT/RT tumour samples. These results demonstrate that fly models can be employed for the identification of clinically relevant pathways in human cancer.

Jeibmann, Astrid; Eikmeier, Kristin; Linge, Anna; Kool, Marcel; Koos, Björn; Schulz, Jacqueline; Albrecht, Stefanie; Bartelheim, Kerstin; Frühwald, Michael C.; Pfister, Stefan M.; Paulus, Werner; Hasselblatt, Martin

2014-06-01

227

Renal tumour anatomical characteristics and functional outcome after partial nephrectomy.  

PubMed

Abstract Objective. Anatomical features of renal tumours may be useful in predicting glomerular filtration rate (GFR) after partial nephrectomy. In this study, anatomical classification systems (ACSs) were compared to predict changes in renal function after surgery. Materials and methods. A group of 294 patients with T1 renal tumours receiving partial nephrectomy between January 2006 and June 2013 were identified from the institutional kidney tumour database. Preoperative images from computed tomography or magnetic resonance imaging were reviewed to assess diameter, PADUA (preoperative aspects and dimensions used for an anatomical) classification score, RENAL (radius, exophytic/endophytic properties of the tumour, nearness of tumour deepest portion to the collecting system or sinus, anterior/posterior descriptor and location relative to polar lines) nephrometry score, centrality index (C index) and renal tumour invasion index (RTII). GFR was estimated using the Modification of Diet in Renal Disease equation preoperatively and 3 months after operation. Linear and logistic regression were applied as statistical methods. Results. Mean tumour diameter was 3.0 ± 2.2 cm (range 1.0-7.0 cm). GFR was 85 ± 22?ml/min/1.73?m² before the operation and 77 ± 21 ml/min/1.73 m² (-8% change) 3 months after the operation. In univariate linear regression, the percentage change in GFR was weakly but statistically significantly associated with surgical approach (p = 0.04), indication for nephron sparing (p = 0.02), preoperative GFR (p < 0.001), PADUA (p = 0.02), RENAL (p = 0.01) and RTII (p = 0.003). In multivariate logistic regression analysis among patients with tumours 3?cm or larger, PADUA (odds ratio 1.55, p = 0.021) and RTII (odds ratio 3.87, p = 0.037) predicted at least a 20% reduction in GFR. Conclusions. Renal tumour ACSs may be clinically useful in predicting changes in renal function after partial nephrectomy in patients with larger tumours. The performance of RTII is equal to that of other ACSs in predicting changes in GFR. PMID:25385687

Nisen, Harry; Heimonen, Petri; Kenttä, Lauri; Visapää, Harri; Nisen, Jessica; Taari, Kimmo

2014-11-11

228

Current state of knowledge on neuroendocrine small bowel tumours: non-systematic review of the literature based on one case  

PubMed Central

More than 60% of neuroendocrine tumours, also called carcinoids, are localised within the gastrointestinal tract. Small bowel neuroendocrine tumours have been diagnosed with increasing frequency over the past 35?years, being the second most frequent tumours of the small intestine. Ileal neuroendocrine tumours diagnosis is late because patients have non-specific symptoms. We have proposed to illustrate as an example the case of a patient, and on its basis, to make a brief review of the literature on small bowel neuroendocrine tumours, resuming several recent changes in the field, concerning classification criteria of these tumours and new recommendations and current advances in diagnosis and treatment. This patient came to our emergency department with a complete bowel obstruction, along with a 2-year history of peristaltic abdominal pain, vomits and diarrhoea episodes. During emergency laparotomy, an ileal stricture was observed, that showed to be a neuroendocrine tumour of the small bowel. PMID:23329706

Simion, Nicolae Irinel; Muntean, Valentin; Fabian, Ovidiu

2013-01-01

229

[The new classification of lung adenocarcinoma].  

PubMed

The new, interdisciplinary IASLC/ATS/ERS classification of lung adenocarcinoma has achieved a considerable impact since its publication in the year 2011. It separates tumours into preinvasive, minimally invasive and invasive subtypes. The preinvasive lesions atypical, adenomatous hyperplasia (AAH) and adenocarcinoma in situ (AIS) together with the minimally invasive adenocarcinoma (MIA), have an excellent prognosis after complete resection with 100 % survival. It enables a reproducible tumour grading by the determination of the predominant histological growth pattern which could be confirmed in several follow-up studies. Thereby the mixed subtype was eliminated which formerly represented about 80 % of all adenocarcinomas. Similarly, the terms bronchioloalveolar adenocarcinoma and bronchioloalveolar tumour growth were eliminated because they represented several distinct entities, specifically the in-situ lesions AAH and ACIS as well as the non-in-situ/invasive tumours like minimally invasive adenocarcinoma, lepidic predominant adenocarcinoma (LPA) and invasive mucinous adenocarcinoma (IMA). Although the classification is based on data from tumour resections it accommodates the fact that most tumours are diagnosed on biopsies and cytological specimens and includes recommendations for an efficient work-up to preserve tissue for molecular testing. Furthermore, the morphological analysis may provide hints for molecular changes including mutations with therapeutic relevance that may enable targeted molecular diagnostics. This review presents essentials facts of the new classification that will be part of the next WHO classification of lung tumors and its follow-up publications. PMID:24150851

Petersen, I

2013-10-01

230

Distribution of endogenous tumour necrosis factor alpha in gliomas.  

PubMed Central

AIMS: To determine the distribution and cellular origin of endogenous tumour necrosis factor alpha (TNF alpha) in the cellular components of human gliomas. METHODS: Frozen sections of 26 gliomas (four astrocytomas (As); two oligoastrocytomas (OA); one ansplastic astrocytoma (AA); one anaplastic oligoastrocytoma (AOA); 18 glioblastomas (GB)) were examined immunohistochemically using antihuman TNF alpha and anti-Leu-M5 (CD11c) antibodies. Additional studies with double immunohistocchemical procedures were performed with anti-glial fibrillary acidic protein and anti-neurofilament antibodies. RESULTS: Eighty per cent of the AA, AOA, and GB (16 of 20) had a positive reaction for TNF alpha, but only 17% of As and OA (one of six) were positive. Positive cells were seen in both the tumour tissue and adjacent brain tissues. TNF alpha protein was detected not only in the tumour cells but also in the endothelium of tumour vessels as well as reactive astrocytes and neurons. CONCLUSIONS: Endogenous TNF alpha is present in cells of various origins in glial tumours including tumour vessels; however, the role of TNF alpha may be different in different types of cells or altered microenvironment. Images PMID:9306934

Maruno, M; Kovach, J S; Kelly, P J; Yanagihara, T

1997-01-01

231

LET-painting increases tumour control probability in hypoxic tumours.  

PubMed

LET-painting was suggested as a method to overcome tumour hypoxia. In vitro experiments have demonstrated a well-established relationship between the oxygen enhancement ratio (OER) and linear energy transfer (LET), where OER approaches unity for high-LET values. However, high-LET radiation also increases the risk for side effects in normal tissue. LET-painting attempts to restrict high-LET radiation to compartments that are found to be hypoxic, while applying lower LET radiation to normoxic tissues. Methods. Carbon-12 and oxygen-16 ion treatment plans with four fields and with homogeneous dose in the target volume, are applied on an oropharyngeal cancer case with an identified hypoxic entity within the tumour. The target dose is optimised to achieve a tumour control probability (TCP) of 95% when assuming a fully normoxic tissue. Using the same primary particle energy fluence needed for this plan, TCP is recalculated for three cases assuming hypoxia: first, redistributing LET to match the hypoxic structure (LET-painting). Second, plans are recalculated for varying hypoxic tumour volume in order to investigate the threshold volume where TCP can be established. Finally, a slight dose boost (5-20%) is additionally allowed in the hypoxic subvolume to assess its impact on TCP. Results. LET-painting with carbon-12 ions can only achieve tumour control for hypoxic subvolumes smaller than 0.5 cm(3). Using oxygen-16 ions, tumour control can be achieved for tumours with hypoxic subvolumes of up to 1 or 2 cm(3). Tumour control can be achieved for tumours with even larger hypoxic subvolumes, if a slight dose boost is allowed in combination with LET-painting. Conclusion. Our findings clearly indicate that a substantial increase in tumour control can be achieved when applying the LET-painting concept using oxygen-16 ions on hypoxic tumours, ideally with a slight dose boost. PMID:24020629

Bassler, Niels; Toftegaard, Jakob; Lühr, Armin; Sørensen, Brita Singers; Scifoni, Emanuele; Krämer, Michael; Jäkel, Oliver; Mortensen, Lise Saksø; Overgaard, Jens; Petersen, Jørgen B

2014-01-01

232

Mediastinal germ cell tumour causing superior vena cava tumour thrombosis.  

PubMed

We report a rare case of a 35-year-old man who presented with a 1-week history of retrosternal chest pain of moderate intensity. A positron emission tomography CT (PET-CT) showed a large fluorodeoxy-glucose (FDG)-avid heterogeneously enhancing necrotic mass in the anterosuperior mediastinum with a focal FDG-avid thrombosis of the superior vena cava (SVC) suggestive of tumour thrombus and vascular invasion. ?-Fetoprotein levels were raised (5690?IU/L). Image guided biopsy of the mediastinal mass was suggestive of non-seminomatous germ cell tumour (NSGCT). The patient received four cycles of BEP (bleomycin, etoposide and cisplatin) along with therapeutic anticoagulation with low-molecular-weight heparin. Follow-up whole body PET-CT revealed complete resolution of mediastinal mass and SVC tumour thrombosis. The documentation of FDG-PET-avid tumour thrombus resolving with chemotherapy supports the concept of circulating tumour cells being important not only in common solid tumours such as breast and colon cancer but also in relatively less common tumours such as NSGCT. The detection of circulating tumour cells could help deploy aggressive regimens upfront. PMID:25809431

Karanth, Suman S; Vaid, Ashok K; Batra, Sandeep; Sharma, Devender

2015-01-01

233

Solid pseudopapillary tumour (Frantz's tumour) of the pancreas in childhood.  

PubMed

An 11-year-old girl presented with acute pancreatitis and mass in the head of the pancreas. MRI revealed a heterogeneous right-upper quadrant retroperitoneal mass measuring 6.8×6.1×5.5 cm arising from the pancreatic head. Endoscopic ultrasound with fine-needle aspirate revealed a solid pseudopapillary tumour (SPT) of the pancreas. The patient underwent a pylorus-preserving Whipple procedure. Pathology confirmed SPT. First described by Frantz, SPT represents less than 3% of all exocrine tumours. It is especially rare in children and shows different clinical features compared with adults. In our patient, tumour cells were arranged at the periphery of fibrovascular cores, but they did not show definite gland formation, keratinisation or cytoplasmic pigment accumulation. A periodic acid-Schiff stain without diastase did not show appreciable glycogen within the tumour cells, classic for Frantz's tumour. The literature, diagnosis, management and pathogenesis on this rare entity in children are reviewed and discussed. PMID:24488660

Escobar, Mauricio Antonio; Bond, Blake J; Schopp, James

2014-01-01

234

Mucinous tumours of appendix and ovary: an overview and evaluation of current practice.  

PubMed

Mucinous lesions of the appendix and ovary are commonly encountered in routine practice. There are several published classification schemes for appendiceal mucinous neoplasms with resultant inconsistent use of terms and clinical doubt. While nomenclature is more settled with regards to ovarian mucinous neoplasms, the difficulty here lies with distinguishing primary from secondary mucinous tumours. This review highlights the terminology and nomenclature for appendiceal mucinous tumours, the relationship with ovarian mucinous neoplasms and pseudomyxoma peritonei, and the features that assist in separating primary from secondary ovarian mucinous tumours. PMID:24265325

Rouzbahman, Marjan; Chetty, Runjan

2014-03-01

235

Republished: mucinous tumours of appendix and ovary: an overview and evaluation of current practice.  

PubMed

Mucinous lesions of the appendix and ovary are commonly encountered in routine practice. There are several published classification schemes for appendiceal mucinous neoplasms with resultant inconsistent use of terms and clinical doubt. While nomenclature is more settled with regards to ovarian mucinous neoplasms, the difficulty here lies with distinguishing primary from secondary mucinous tumours. This review highlights the terminology and nomenclature for appendiceal mucinous tumours, the relationship with ovarian mucinous neoplasms and pseudomyxoma peritonei, and the features that assist in separating primary from secondary ovarian mucinous tumours. PMID:25583738

Rouzbahman, Marjan; Chetty, Runjan

2015-01-01

236

Molecular targets in pituitary tumours  

Microsoft Academic Search

Pituitary tumours are associated with unrestrained secretion and subsequent action of trophic hormones. One approach to therapy involves suppressing pituitary-hormone hypersecretion without compromising endogenous pituitary function. Identification of novel neuroendocrine-receptor targets has enabled the development of safe and effective receptor ligands that can be used to treat pituitary tumours and associated hormonal excess. Some of these agents, such as somatostatin

Anthony P. Heaney; Shlomo Melmed

2004-01-01

237

Complications of mediastinal neural tumours  

PubMed Central

Thirty-two mediastinal neural tumours were seen in the East Anglian Regional Thoracic Surgical Unit at Cambridge between October 1952 and July 1970. The descending order of frequency was neurofibroma, ganglioneuroma, neurilemmoma, neurofibrosarcoma, and neuroblastoma. The literature relating to these tumours is reviewed and the pathological and clinical complications encountered in this series and in the literature are described. PMID:4327710

Parish, Christopher

1971-01-01

238

Tumour Banking: The Spanish Design  

Microsoft Academic Search

In the last decade the technical advances in high throughput techniques to analyze DNA, RNA and proteins have had a potential major impact on prevention, diagnosis, prognosis and treatment of many human diseases. Key pieces in this process, mainly thinking about the future, are tumour banks and tumour bank networks. To face these challenges, diverse suitable models and designs can

M. M. Morente; E. de Alava; P. L. Fernandez

2007-01-01

239

Classification of binary intentions for individuals with impaired oculomotor function: ‘eyes-closed’ SSVEP-based brain-computer interface (BCI)  

NASA Astrophysics Data System (ADS)

Objective. Some patients suffering from severe neuromuscular diseases have difficulty controlling not only their bodies but also their eyes. Since these patients have difficulty gazing at specific visual stimuli or keeping their eyes open for a long time, they are unable to use the typical steady-state visual evoked potential (SSVEP)-based brain-computer interface (BCI) systems. In this study, we introduce a new paradigm for SSVEP-based BCI, which can be potentially suitable for disabled individuals with impaired oculomotor function. Approach. The proposed electroencephalography (EEG)-based BCI system allows users to express their binary intentions without needing to open their eyes. A pair of glasses with two light emitting diodes flickering at different frequencies was used to present visual stimuli to participants with their eyes closed, and we classified the recorded EEG patterns in the online experiments conducted with five healthy participants and one patient with severe amyotrophic lateral sclerosis (ALS). Main results. Through offline experiments performed with 11 participants, we confirmed that human SSVEP could be modulated by visual selective attention to a specific light stimulus penetrating through the eyelids. Furthermore, the recorded EEG patterns could be classified with accuracy high enough for use in a practical BCI system. After customizing the parameters of the proposed SSVEP-based BCI paradigm based on the offline analysis results, binary intentions of five healthy participants were classified in real time. The average information transfer rate of our online experiments reached 10.83 bits min-1. A preliminary online experiment conducted with an ALS patient showed a classification accuracy of 80%. Significance. The results of our offline and online experiments demonstrated the feasibility of our proposed SSVEP-based BCI paradigm. It is expected that our ‘eyes-closed’ SSVEP-based BCI system can be potentially used for communication of disabled individuals with impaired oculomotor function.

Lim, Jeong-Hwan; Hwang, Han-Jeong; Han, Chang-Hee; Jung, Ki-Young; Im, Chang-Hwan

2013-04-01

240

Survival of patients with nonseminomatous germ cell cancer: a review of the IGCC classification by Cox regression and recursive partitioning  

Microsoft Academic Search

The International Germ Cell Consensus (IGCC) classification identifies good, intermediate and poor prognosis groups among patients with metastatic nonseminomatous germ cell tumours (NSGCT). It uses the risk factors primary site, presence of nonpulmonary visceral metastases and tumour markers alpha-fetoprotein (AFP), human chorionic gonadotrophin (HCG) and lactic dehydrogenase (LDH). The IGCC classification is easy to use and remember, but lacks flexibility.

M R van Dijk; E W Steyerberg; S P Stenning; E Dusseldorp; J D F Habbema; van Dijk

2004-01-01

241

Radiosensitization of tumours by porphyrins.  

PubMed

Our previous data indicate, that hematoporphyrin dimethyl ether (HPde) can totally inhibit the growth of aggressive Ehrlich ascite tumour, when combined with low doses (2Gy) of ionizing radiation. Taking into account these findings, it appears of particular interest to evaluate the dependence of radiosensitizing efficiency of porphyrins on tumour aggressiveness. For this purpose two experimental tumour models (aggressive murine Ehrlich ascite carcinoma, (EAT), and not-aggressive hepatoma MH-22A) were used. Moreover, radiosensitizing properties of three porphyrin-type compounds of different chemical heterogeneity were evaluated (hematoporphyrin dimethyl ether (HPde), photofrin II (PII) and hematoporphyrin derivative (HPD)). Data obtained indicate, that HPde is the most effective one in this context (HPde>PII>HPD). It is important to note, that only the aggressive EAT tumours were radiosensitized by these dyes. No signs of radiosensitization (inhibition of tumour growth, injury of tumour tissue, evaluated by histological analysis) were observed in not-aggressive MH-22A hepatoma. Moreover, it was shown, that ligands of peripheral benzodiazepine receptors (PBR) might diminish the cell growth in aggressive EAT, but not in not-aggressive MH-22A hepatoma. The mechanism of radiosensitization by porphyrins, proposed in our previous studies, was strongly confirmed by these data. Actually, dicarboxylic porphyrins, being ligands of PBR, which are highly expressed in just aggressive tumours, can inhibit tumour cell proliferation and act in concert with ionizing radiation. Thus, combination of porphyrin and ionising radiation reflects the action of two antiproliferative factors, what eventually increases the response of aggressive tumours to the low doses of ionising radiation. PMID:15946797

Luksiene, Zivile; Juzenas, Petras; Moan, Johan

2006-04-01

242

Brain drug delivery technologies: novel approaches for transporting therapeutics  

Microsoft Academic Search

The blood–brain barrier (BBB) denies many therapeutic agents access to brain tumours and other diseases of the central nervous system (CNS). Despite remarkable advances in our understanding of the mechanisms involved in the development of the brain diseases and the actions of neuroactive agents, drug delivery to the brain remains a challenge. For more than 20 years, extensive efforts have

Jamal Temsamani; Jean-Michel Scherrmann; Anthony R Rees; Michel Kaczorek

2000-01-01

243

How Does Interferon Inhibit Tumour Growth?: Discussion  

Microsoft Academic Search

Interferon can inhibit tumour growth in experimental animals and in some patients with benign and malignant tumours. There is experimental evidence to suggest that several mechanisms may be involved: a direct effect on the tumour or an indirect effect via the host, or both. Thus, interferon may slow the rate of tumour cell multiplication and this may lead to cell

Michael Stoker

1982-01-01

244

Management of non-epithelial ovarian tumours.  

PubMed

Ovarian tumours of non-epithelial origin are less common than those of epithelial origin but must be distinguished from these as their natural history and management differ. As these tumours are rare, histological review by an expert in the field is essential. There have been no randomised trials to outline the management of these tumours and therefore this paper represents a review of descriptive data. Non-epithelial ovarian tumours, which represent approximately 50% of all ovarian tumours and approximately 25% of malignant ovarian tumours, are outlined. Lymphomas and metastatic tumours should be treated the same as when found in other sites and will not be discussed further. PMID:10461054

Bridgewater, J A; Rustin, G J

1999-01-01

245

Can experimental models of rodent implantation glioma be improved? A study of pure and mixed glioma cell line tumours.  

PubMed

To evaluate the hypothesis that co-implantation of different rodent glioma cell lines might result in experimental brain tumours that more closely resemble human gliomas the neuropathology and immunocytochemical features of implantation gliomas derived from single cell lines (C6, A15A5, F98), two cell lines admixed 50:50 prior to implantation (C6 + F98 and C6 + A15A5) and three cell lines equally admixed (C6 + A15A5 + F98) was studied in the adult Wistar rat. Tumours grew consistently following implantation of the single and the two admixed cell lines, however tumour growth following triple mix implantation was considerably and consistently impaired. The tumours derived from admixed cell lines showed regional heterogeneity with areas characteristic of both the primary cell lines. Foci of lymphocytic infiltrates, tumoural necrosis, often with pseudopallisading, and peritumoural edema were consistent features of all tumours. Limited parenchymal and more extensive perivascular tumoural invasion was seen predominantly in tumours containing the C6 cell line. There were no significant differences in GFAP, vimentin and HSP70 staining between the mixed tumours, although the pure F98 and A15A5 tumours were, unlike the pure C6 gliomas, S-100 negative. Using PCNA expression as a measure of the tumour proliferation all except the tumours derived from the three cell lines mix, which had a staining index of 7-10%, had focal staining indices in viable tumour of between 40-80%. There was focal positive staining in both perilesional brain and in regions of all tumours for the macrophage markers ED-1 and ED-2. None of the three cell lines stained in vitro for either ED1 and ED2 but all were constitutively positive in vitro for OX-6, a proposed marker for antigen presenting cells. The macrophage and lymphocytic response suggest a vigorous but largely ineffective immunological response had been mounted against all tumours. The consistent failure of the triple mix tumours to grow is unexplained. This work has shown the feasibility of producing 'mixed' cell line experimental gliomas by combining two cell lines at the time of innoculation. However, the relative failure to produce (i) mixed tumours that have properties not inherent to either parent cell line and (ii) implantation glioma with three cell lines suggest there are limits to this approach. Admixture of cell lines at the time of implantation therefore does not make experimental glioma models that more closely resemble natural gliomas, and also has some particular disadvantages. This experimental approach is therefore not recommended for use in the study of tumour biology and in evaluating the effectiveness of novel therapies. PMID:9524101

Whittle, I R; Macarthur, D C; Malcolm, G P; Li, M; Washington, K; Ironside, J W

1998-02-01

246

Brain metastasis from medullary thyroid carcinoma  

PubMed Central

The brain is an exceedingly rare site of metastasis in medullary thyroid carcinoma (MTC). A 50-year-old female who had a history of micro-MTC 11 years prior developed a cerebellar metastasis which was incidentally discovered. Imaging revealed a right cerebellar hemispheric mass with contrast enhancement on CT scans. Histopathologic exam demonstrated a metastatic tumour composed of nodules and sheets of large tumour cells with abundant cytoplasm. Immunohistochemistry confirmed the origin from a MTC. This case report highlights the unique features of an unusual metastatic brain tumour, which followed an indolent course for a long time despite multiple distant metastases. PMID:22802478

Börcek, P; Asa, S L; Gentili, F; Ezzat, S; Kiehl, T-R

2010-01-01

247

Midgut carcinoid tumours. CT appearance.  

PubMed

CT was performed on 80 patients referred for staging and treatment of histologically verified midgut carcinoid tumours. In 17 cases (21%) CT was normal in spite of biochemical signs of tumour (increased U-5-HIAA). The most common finding was liver metastases in 54/80 (68%) of patients. Mesenteric metastases, usually as a soft tissue mass at the mesenteric root, were found in 17/80 (21%). Retroperitoneal adenopathy was found in 19/80 (24%). During a follow-up time of 3 months to 10 years (median 3 years) 445 additional CT examinations were performed on 77 patients. In 39 of these, progressive disease (new lesions) was found after a median time of 15 months (range 3 months-6.5 years). CT is poor in detecting primary carcinoid tumours but helpful in evaluating the extent of tumour spread before surgical exploration and during follow-up once the diagnosis has been established. PMID:7619613

Sugimoto, E; Lörelius, L E; Eriksson, B; Oberg, K

1995-07-01

248

Inhibition in Multiclass Classification  

Microsoft Academic Search

The role of inhibition is investigated in a multiclass support vector machine formalism inspired by the brain structure of insects. The so-called mushroom bodies have a set of output neurons, or classification functions, that compete with each other to encode a particular input. Strongly active output neurons depress or inhibit the remaining outputs without knowing which is correct or incorrect.

Ramón Huerta; Shankar Vembu; José M. Amigó; Thomas Nowotny; Charles Elkan

2012-01-01

249

Classification 1: Classification Scheme  

NSDL National Science Digital Library

This Science NetLinks lesson, first of a two-part series will show students that many kinds of living things can be sorted into groups in many ways using various features to decide which things belong to which group and that classification schemes will vary with purpose.ContextThis lesson is the first of a two-part series on classification. This lesson is intended to supplement students' direct investigations by using the Internet to expose students to a variety of living organisms, as well as encourage them to start developing classification schemes of their own.

Science Netlinks

2001-10-20

250

Primitive neuroectodermal adrenal gland tumour.  

PubMed

Ewing's sarcoma, also called primitive neuroectodermal tumour of the adrenal gland, is extremely rare. Only a few cases have been reported in the literature. We report on a woman with adult-onset primitive neuroectodermal tumour of the adrenal gland presenting with progressive flank pain. Computed tomography confirmed an adrenal tumour with invasion of the left diaphragm and kidney. Radical surgery was performed and the pain completely resolved; histology confirmed the presence of primitive neuroectodermal tumour, for which she was given chemotherapy. The clinical presentation of this condition is non-specific, and a definitive diagnosis is based on a combination of histology, as well as immunohistochemical and cytogenic analysis. According to the literature, these tumours demonstrate rapid growth and aggressive behaviour but there are no well-established guidelines or treatment strategies. Nevertheless, surgery remains the mainstay of local disease control; curative surgery can be performed in most patients. Adjuvant chemoirradiation has been advocated yet no consensus is available. The prognosis of patients with primitive neuroectodermal tumours remains poor. PMID:25307073

Tsang, Y P; Lang, Brian H H; Tam, S C; Wong, K P

2014-10-01

251

Contemporary methods of therapy and follow-up of neuroendocrine tumours of the gastrointestinal tract and the pancreas  

PubMed Central

The growing interest in neuroendocrine tumours is due to the dynamic growth of detection of this type of cancer. Neuroendocrine tumours (neuroendocrine neoplasms – NENs / neuroendocrine tumours – NETs) derive from glands, groups of endocrine cells and diffuse neuroendocrine system cells. Mainly they derive from the gastrointestinal tract (gastroenteropancreatic-neuroendocrine tumours – GEP-NETs). Currently the modified WHO classification from 2010 is widely used. An important element in the choice of treatment is histological maturity based on mitotic activity and on assessment of proliferation activity (Ki-67). The treatment of choice is surgery. In most cases, complete surgical removal is impossible because of the advanced staging at the time of diagnosis. In well-differentiated neoplasms where the expression of somatostatin receptors is expected, patients are qualified for somatostatin analogues therapy. Poorly differentiated lesions are qualified for chemotherapy. In the guidelines of ENETS (European Neuroendocrine Tumor Society) from 2007 the rules concerning monitoring depending on the WHO classification were specified. PMID:23788913

Fischbach, Jakub; Kami?ski, Grzegorz; Rucha?a, Marek

2012-01-01

252

Reappraisal of the so-called ‘villous tumours’ of the rectosigmoid, based on histological, immunohistochemical and genotypic features  

PubMed Central

Background Villous tumours of the rectosigmoid are historically defined as broad-based lesions associated with secretory diarrhoea. Objective This study aimed to perform a reappraisal of these tumours, on the basis of newly introduced histological, immunohistochemical and molecular parameters. Methods For this study, 22 villous tumours, diagnosed by endoscopic criteria (19 Paris 0–IIa, three Paris 0–Is), were evaluated according to WHO classification. Microsatellite instability status, KRAS and BRAF mutations, MGMT status of villous tumours and associated invasive carcinoma were determined. Results The 22 villous tumours fell into four groups: 1) nine villous adenomas, 2) six tubulovillous adenomas, 3) three filiform traditional serrated adenomas, and 4) four traditional serrated adenomas with conventional dysplasia. Filiform serrated adenomas displayed a distinctive endoscopic protruding pattern (Paris 0-Is). Villous adenomas were strongly associated with secretory diarrhoea. All the villous tumours were microsatellite stable. Five tumours exhibited MGMT abnormalities. KRAS mutations were frequent in villous adenomas, whereas BRAF mutations were essentially detected in serrated lesions. Invasive carcinomas (n?=?7) maintained the histopathological and molecular imprint of the prior villous tumour. Conclusion The rectosigmoid villous tumours are histologically and molecularly heterogeneous, including serrated neoplasias. Endoscopic and clinical findings are predictive of the histopathological diagnosis of some of these distinct entities. PMID:25083289

Küry, Sébastien; Coron, Emmanuel; Bézieau, Stéphane; Laboisse, Christian L; Mosnier, Jean-François

2014-01-01

253

Pitfalls in colour photography of choroidal tumours  

PubMed Central

Colour imaging of fundus tumours has been transformed by the development of digital and confocal scanning laser photography. These advances provide numerous benefits, such as panoramic images, increased contrast, non-contact wide-angle imaging, non-mydriatic photography, and simultaneous angiography. False tumour colour representation can, however, cause serious diagnostic errors. Large choroidal tumours can be totally invisible on angiography. Pseudogrowth can occur because of artefacts caused by different methods of fundus illumination, movement of reference blood vessels, and flattening of Bruch's membrane and sclera when tumour regression occurs. Awareness of these pitfalls should prevent the clinician from misdiagnosing tumours and wrongfully concluding that a tumour has grown. PMID:23238442

Schalenbourg, A; Zografos, L

2013-01-01

254

[18F]FLT PET for diagnosis and staging of thoracic tumours.  

PubMed

The nucleoside analogue 3'-deoxy-3'-[18F]fluorothymidine (FLT) has been introduced for imaging of tumour cell proliferation by positron emission tomography (PET). This study evaluated the use of FLT in patients with thoracic tumours prior to treatment. Whole-body FLT PET was performed in 16 patients with 18 tumours [17 thoracic tumours (nine non-small cell lung cancers, five oesophageal carcinomas, two sarcomas, one Hodgkin's lymphoma) and one renal carcinoma] before treatment. Fluorine-18 fluorodeoxyglucose (FDG) PET was performed for comparison except in those patients with oesophageal carcinoma. For semi-quantitative analysis, the average and maximum standardised uptake values (avgSUV and maxSUV, respectively) (FLT, 114+/-20 min p.i.; FDG, 87+/-8 min p.i.; 50% isocontour region of interest) was calculated. All 17 thoracic tumours and 19/20 metastases revealed significant FLT accumulation, resulting in easy delineation from surrounding tissue. The additional small grade 1 renal carcinoma was not detected with either FLT or FDG. In most lung tumours (avgSUV 1.5-8.2) and metastases, FLT showed intense uptake. However, one of two spinal bone metastases was missed owing to the high physiological FLT uptake in the surrounding bone marrow. Oesophageal carcinoma primaries (avgSUV 2.7-10.0) and occasional metastases showed particularly favourable tumour/non-tumour contrast. Compared with FDG, tumour uptake of FLT was lower (avgSUV, P=0.0006; maxSUV, P=0.0001), with a significant linear correlation (avgSUV, r2=0.45; maxSUV, r2=0.49) between FLT and FDG. It is concluded that FLT PET accurately visualises thoracic tumour lesions. In the liver and the bone marrow, high physiological FLT uptake hampers detection of metastases. On the other hand, FLT may be favourable for imaging of brain metastases owing to the low physiological uptake. PMID:12898201

Dittmann, Helmut; Dohmen, Bernhard Matthias; Paulsen, Frank; Eichhorn, Kai; Eschmann, Susanne Martina; Horger, Marius; Wehrmann, Manfred; Machulla, Hans Juergen; Bares, Roland

2003-10-01

255

Classification 1: Classification Scheme  

NSDL National Science Digital Library

This lesson shows students that living things can be sorted into groups in many ways using various features to decide which things belong to which group and that classification schemes will vary with purpose. It is the first of a two-part series on classification. At this grade level, students should have the opportunity to learn about an increasing variety of living organisms, both the familiar and the exotic, and should become more precise in identifying similarities and differences among them. Firsthand observation of the living environment is essential for students to gain an understanding of the differences among organisms. This lesson is intended to supplement direct investigations made by students by using the Internet to expose them to a variety of living organisms, as well as encourage them to start developing classification schemes of their own.

256

Anti-tumour activity of oncolytic Western Reserve vaccinia viruses in canine tumour cell lines, xenografts, and fresh tumour biopsies.  

PubMed

Cancer is one of the most common reasons for death in dogs. One promising approach is oncolytic virotherapy. We assessed the oncolytic effect of genetically modified vaccinia viruses in canine cancer cells, in freshly excised tumour biopsies, and in mice harbouring canine tumour xenografts. Tumour transduction efficacy was assessed using virus expressing luciferase or fluorescent marker genes and oncolysis was quantified by a colorimetric cell viability assay. Oncolytic efficacy in vivo was evaluated in a nude mouse xenograft model. Vaccinia virus was shown to infect most tested canine cancer cell lines and primary surgical tumour tissues. Virus infection significantly reduced tumour growth in the xenograft model. Oncolytic vaccinia virus has antitumour effects against canine cancer cells and experimental tumours and is able to replicate in freshly excised patient tumour tissue. Our results suggest that oncolytic vaccinia virus may offer an effective treatment option for otherwise incurable canine tumours. PMID:25302859

Autio, K; Knuuttila, A; Kipar, A; Ahonen, M; Parviainen, S; Diaconu, I; Kanerva, A; Hakonen, T; Vähä-Koskela, M; Hemminki, A

2014-10-10

257

Effects of childhood body size on breast cancer tumour characteristics  

PubMed Central

Introduction Although a role of childhood body size in postmenopausal breast cancer risk has been established, less is known about its influence on tumour characteristics. Methods We studied the relationships between childhood body size and tumour characteristics in a Swedish population-based case-control study consisting of 2,818 breast cancer cases and 3,111 controls. Our classification of childhood body size was derived from a nine-level somatotype. Relative risks were estimated by odds ratios with 95% confidence intervals, derived from fitting unconditional logistic regression models. Association between somatotype at age 7 and tumour characteristics were evaluated in a case-only analysis where P values for heterogeneity were obtained by performing one degree of freedom trend tests. Results A large somatotype at age 7 was found to be associated with decreased postmenopausal breast cancer risk. Although strongly associated with other risk factors such as age of menarche, adult body mass index and mammographic density, somatotype at age 7 remained a significant protective factor (odds ratio (OR) comparing large to lean somatotype at age 7 = 0.73, 95% confidence interval (CI) = 0.58-0.91, P trend = 0.004) after adjustment. The significant protective effect was observed within all subgroups defined by estrogen receptor (ER) and progesterone receptor (PR) status, with a stronger effect for ER-negative (0.40, 95% CI = 0.21-0.75, P trend = 0.002), than for ER-positive (0.80, 95% CI = 0.62-1.05, P trend = 0.062), tumours (P heterogeneity = 0.046). Somatotype at age 7 was not associated with tumour size, histology, grade or the presence or absence of metastatic nodes. Conclusions Greater body size at age 7 is associated with a decreased risk of postmenopausal breast cancer, and the associated protective effect is stronger for the ER-negative breast cancer subtype than for the ER-positive subtype. PMID:20398298

2010-01-01

258

Potassium channels as tumour markers.  

PubMed

An increasing number of ion channels are being found to be causally involved in diseases, giving rise to the new field of "channelopathies". Cancer is no exception, and several ion channels have been linked to tumour progression. Among them is the potassium channel EAG (Ether-a-go-go). Over 75% of tumours have been tested positive using a monoclonal antibody specific for EAG, while inhibition of this channel decreased the proliferation of EAG expressing cells. The inhibition of EAG is accomplished using RNA interference, functional anti-EAG1 antibodies, or (unspecific) EAG channel blockers. Fluorescently labelled recombinant Fab fragments recognizing EAG allow the distribution of EAG to be visualized in an in vivo mouse tumour model. PMID:16783874

Stühmer, Walter; Alves, Frauke; Hartung, Franziska; Zientkowska, Marta; Pardo, Luis A

2006-05-22

259

Apoptosis is not correlated with the presence of CD57 + NK-cells in brain metastases  

Microsoft Academic Search

Summary ¶ Background. Cell apoptosis in solid tumours has been related to immunological attack by NK-cells. The purpose of the present study is to verify in the tissue of brain metastases a possible relationship among the degree of NK-cell infiltration and the number of apoptotic tumour cells. Methods. Twenty brain metastases whose tumour cells expressed CD95 (Fas\\/APO1) have been studied.

J. Vaquero; M. Zurita; C. Aguayo; S. Coca

2003-01-01

260

The attitudes of brain cancer patients and their caregivers towards death and dying: a qualitative study  

Microsoft Academic Search

BACKGROUND: Much money and energy has been spent on the study of the molecular biology of malignant brain tumours. However, little attention has been paid to the wishes of patients afflicted with these incurable tumours, and how this might influence treatment considerations. METHODS: We interviewed 29 individuals – 7 patients dying of a malignant brain tumor and 22 loved ones.

Nir Lipsman; Abby Skanda; Jonathan Kimmelman; Mark Bernstein

2007-01-01

261

Spinal cord tumours: advances in genetics and their implications for treatment  

PubMed Central

Tumours of the spinal cord, although rare, are associated with high morbidity. Surgical resection remains the primary treatment for patients with this disease, and offers the best chance for cure. Such surgical procedures, however, carry substantial risks such as worsening of neurological deficit, paralysis and death. New therapeutic avenues for spinal cord tumours are needed, but genetic studies of the molecular mechanisms governing tumourigenesis in the spinal cord are limited by the scarcity of high-quality human tumour samples. Many spinal cord tumours have intracranial counterparts that have been extensively studied, but emerging data show that the tumours are genetically and biologically distinct. The differences between brain and spine tumours make extrapolation of data from one to the other difficult. In this Review, we describe the demographics, genetics and current treatment approaches for the most commonly encountered spinal cord tumours—namely, ependymomas, astrocytomas, haemangioblastomas and meningiomas. We highlight advances in understanding of the biological basis of these lesions, and explain how the latest progress in genetics and beyond are being translated to improve patient care. PMID:23528542

Zadnik, Patricia L.; Gokaslan, Ziya L.; Burger, Peter C.; Bettegowda, Chetan

2014-01-01

262

Neurosurgical Concepts and Approaches for Orbital Tumours  

Microsoft Academic Search

Orbital tumours are lesions that appear within the orbital craniofacial borders. To this end, treatment of these tumours is\\u000a assured by teams of different specialists. Furthermore, these pathologies are different in adults and in children. We have\\u000a endeavoured, in this chapter, to highlight the specifically neurosurgical features of orbital tumours or, to be more precise,\\u000a tumours affecting the posterior two

J. C. Marchal; T. Civit

263

A 5-hydroxytryptophan-secreting carcinoid tumour  

PubMed Central

An atypical case of the malignant carcinoid syndrome, associated with multiple peptic ulcers, is described. The tumour cells were argyrophil but not argentaffin, and the tumour was found to contain 5-hydroxytryptophan (5-H.T.P.) but not 5-hydroxytryptamine (5-H.T.). This aberrant biochemical behaviour was associated with the virtual absence of 5-H.T.P.-decarboxylase from the tumour tissue. The tumour contained notable quantities of histamine. PMID:14018107

Campbell, A. C. P.; Gowenlock, A. H.; Platt, D. S.; Snow, P. J. D.

1963-01-01

264

Tumour vasculature--a potential therapeutic target.  

PubMed Central

The tumour vasculature is vital for the establishment, growth and metastasis of solid tumours. Its physiological properties limit the effectiveness of conventional anti-cancer strategies. Therapeutic approaches directed at the tumour vasculature are reviewed, suggesting the potential of anti-angiogenesis and the targeting of vascular proliferation antigens as cancer treatments. PMID:7543770

Baillie, C. T.; Winslet, M. C.; Bradley, N. J.

1995-01-01

265

Lymphogenous spread of an intravascular bronchioloalveolar tumour  

Microsoft Academic Search

A 56-year-old lady with distinct clinical symptoms was found to have an intravascular bronchioloalveolar tumour. The aetiology and pathogenesis of this disease are unknown; both a bronchoalveolar and a vascular origin of the tumour are discussed in the literature. For the first time, lymphatic spread of tumour to the lymphatic nodes of the hili of the lungs was encountered.

H. J. C. Wenisch; M. Lulay

1980-01-01

266

Tumour immunotherapy — leukocytes take up the fight  

Microsoft Academic Search

The immune system can promote the elimination of tumours, but often immune responses are modulated or suppressed by the tumour microenvironment. In this joint Focus from Nature Reviews Cancer and Nature Reviews Immunology, leading researchers describe our current understanding of the complex interactions that occur between the immune system and tumour cells, and discuss how the power of the immune

Gemma K. Alderton; Yvonne Bordon

2012-01-01

267

A model for intratumoural chemotherapy in the rat brain  

Microsoft Academic Search

Summary To achieve the best reproducibility in rat brain tumour models several injection techniques have been used. Although stereotactic cell injections have proved to be effective and reliable, they are expensive and time consuming. A new permanently implanted device is presented here. It allows precise cell delivery for best tumour reproducibility, and it can be left in place for future

M. Saini; F. Roser; M. Samii; M. Bellinzona

2004-01-01

268

Viruses and tumours – an update  

Microsoft Academic Search

In the 40 years since the publication of the article by Harris (Eur J Cancer 1965, 1, 183–188), considerable progress has been made towards the understanding of the contribution of infectious agents to the development of tumours. It is estimated that 15–20% of human malignancies may have an infectious aetiology. This article attempts to summarise the current level of our

Simon J Talbot; Dorothy H Crawford

2004-01-01

269

Drug penetration in solid tumours  

Microsoft Academic Search

To be most effective anticancer drugs must penetrate tissue efficiently, reaching all the cancer cells that comprise the target population in a concentration sufficient to exert a therapeutic effect. Most research into the resistance of cancers to chemotherapy has concentrated on molecular mechanisms of resistance, whereas the role of limited drug distribution within tumours has been neglected. We summarize the

Andrew I. Minchinton; Ian F. Tannock

2006-01-01

270

Tumours of the nervous system  

PubMed Central

Tumours of the nervous system of animals are not as rare as has been commonly believed. In dogs, especially the brachycephalic breeds, these tumours occur as frequently as in man. The tumours are grouped according to tissue of origin as follows: nerve cells, neuroepithelium, glia, peripheral nerves and nerve sheaths, meninges and vessels, the pineal and pituitary glands, and the craniopharyngeal duct. Tumours of the glia are relatively common and are divided into the following types: astrocytoma, oligodendroglioma, glioblastoma, spongioblastoma, medulloblastoma, and unclassified gliomas. ImagesFig. 21Fig. 22Fig. 23Fig. 24Fig. 33Fig. 34Fig. 35Fig. 36Fig. 13Fig. 14Fig. 15Fig. 16Fig. 9Fig. 10Fig. 11Fig. 12Fig. 17Fig. 18Fig. 19Fig. 20Fig. 29Fig. 30Fig. 31Fig. 32Fig. 5Fig. 6Fig. 7Fig. 8Fig. 25Fig. 26Fig. 27Fig. 28Fig. 1Fig. 2Fig. 3Fig. 4Fig. 37Fig. 38 PMID:4371739

Fankhauser, R.; Luginbühl, H.; McGrath, J. T.

1974-01-01

271

Colorectal tumours and pit pattern  

Microsoft Academic Search

AIMS--To investigate the morphological and histopathological associations between an individual pit seen on stereomicroscopy or magnifying colonoscopy and an individual crypt seen in histological sections; and to examine these associations in colorectal tumours. METHODS--Fourteen thousand and twenty three cases were examined by colonoscope at Akita Red Cross Hospital. The surface mucosal pits of the lesions were observed using a magnifying

S Kudo; S Hirota; T Nakajima; S Hosobe; H Kusaka; T Kobayashi; M Himori; A Yagyuu

1994-01-01

272

06/11/2001: sim-pl.doc 1 Tumour grading from Magnetic Resonance Spectroscopy  

E-print Network

06/11/2001: sim-pl.doc 1 Tumour grading from Magnetic Resonance Spectroscopy: a comparison performance using a dataset comprising 41 magnetic resonance spectra acquired in vivo from two grades of brain and by application to a test sample in a retrospective study. KEYWORDS: Magnetic resonance; spectroscopy; model

Lisboa, Paulo

273

Mobile phones and head tumours. The discrepancies in cause-effect relationships in the epidemiological studies - how do they arise?  

PubMed Central

Background Whether or not there is a relationship between use of mobile phones (analogue and digital cellulars, and cordless) and head tumour risk (brain tumours, acoustic neuromas, and salivary gland tumours) is still a matter of debate; progress requires a critical analysis of the methodological elements necessary for an impartial evaluation of contradictory studies. Methods A close examination of the protocols and results from all case-control and cohort studies, pooled- and meta-analyses on head tumour risk for mobile phone users was carried out, and for each study the elements necessary for evaluating its reliability were identified. In addition, new meta-analyses of the literature data were undertaken. These were limited to subjects with mobile phone latency time compatible with the progression of the examined tumours, and with analysis of the laterality of head tumour localisation corresponding to the habitual laterality of mobile phone use. Results Blind protocols, free from errors, bias, and financial conditioning factors, give positive results that reveal a cause-effect relationship between long-term mobile phone use or latency and statistically significant increase of ipsilateral head tumour risk, with biological plausibility. Non-blind protocols, which instead are affected by errors, bias, and financial conditioning factors, give negative results with systematic underestimate of such risk. However, also in these studies a statistically significant increase in risk of ipsilateral head tumours is quite common after more than 10 years of mobile phone use or latency. The meta-analyses, our included, examining only data on ipsilateral tumours in subjects using mobile phones since or for at least 10 years, show large and statistically significant increases in risk of ipsilateral brain gliomas and acoustic neuromas. Conclusions Our analysis of the literature studies and of the results from meta-analyses of the significant data alone shows an almost doubling of the risk of head tumours induced by long-term mobile phone use or latency. PMID:21679472

2011-01-01

274

Neurofibromatosis type 1-associated tumours: Their somatic mutational spectrum and pathogenesis  

PubMed Central

Somatic gene mutations constitute key events in the malignant transformation of human cells. Somatic mutation can either actively speed up the growth of tumour cells or relax the growth constraints normally imposed upon them, thereby conferring a selective (proliferative) advantage at the cellular level. Neurofibromatosis type-1 (NF1) affects 1/3,000-4,000 individuals worldwide and is caused by the inactivation of the NF1 tumour suppressor gene, which encodes the protein neurofibromin. Consistent with Knudson's two-hit hypothesis, NF1 patients harbouring a heterozygous germline NF1 mutation develop neurofibromas upon somatic mutation of the second, wild-type, NF1 allele. While the identification of somatic mutations in NF1 patients has always been problematic on account of the extensive cellular heterogeneity manifested by neurofibromas, the classification of NF1 somatic mutations is a prerequisite for understanding the complex molecular mechanisms underlying NF1 tumorigenesis. Here, the known somatic mutational spectrum for the NF1 gene in a range of NF1-associated neoplasms --including peripheral nerve sheath tumours (neurofibromas), malignant peripheral nerve sheath tumours, gastrointestinal stromal tumours, gastric carcinoid, juvenile myelomonocytic leukaemia, glomus tumours, astrocytomas and phaeochromocytomas -- have been collated and analysed. PMID:22155606

2011-01-01

275

Spectral classification  

NASA Astrophysics Data System (ADS)

Taxonomic classification of astronomically observed stellar objects is described in terms of spectral properties. Stars receive a classification containing a letter, number, and a Roman numeral, which relates the star to other stars of higher or lower Roman numerals. The citation indicates the stellar chromatic emission in relation to the wavelengths of other stars. Standards are chosen from the available objects detected. Various classification schemes such as the MK, HD, and the Barbier-Chalonge-Divan systems are defined, including examples of indexing differences. Details delineating the separations between classifications are discussed with reference to the information content in spectral and in photometric classification schemes. The parameters usually used for classification include the temperature, luminosity, reddening, binarity, rotation, magnetic field, and elemental abundance or composition. The inclusion of recently discovered extended wavelength characteristics in nominal classifications is outlined, together with techniques involved in automated classification.

Jaschek, C.

276

Clinico-pathological characteristics of different types of immunodeficiency-associated smooth muscle tumours.  

PubMed

Rare Epstein-Barr virus (EBV)+ smooth muscle tumours (SMT) manifest typically under immunosuppression. Three major subtypes are known: human immunodeficiency virus-associated (HIV-SMT), after transplantation (PTSMT) or associated with congenital immunodeficiency syndromes (CI-SMT). So far, there are no analyses which compare the clinico-pathological characteristics of all three subtypes. Case reports and case series on these three tumour types were collected (1990-2012). Meta-data analysis was performed for identification of similarities and differences. A total of 73 HIV-SMT, 66 PTSMT and 9 CI-SMT were evaluated. There was a slight female predominance (55-67%). Children were affected nearly equally in HIV-SMT (33%) and PTSMT (35%), while all CI-SMT occurred in children. HIV-SMT manifested preferentially in the central nervous system, gut/liver, skin, lungs/larynx/pharynx and adrenal glands. PTSMT were predominantly found in the liver, lungs/larynx/pharynx, gut/spleen and brain. CI-SMT were often found in lungs/larynx, brain, liver, adrenal glands and spleen. Antecedent EBV+ lymphoproliferations manifested more often in PTSMT. In all three tumour subtypes, survival analyses did not show any significant differences regarding surgical therapeutic approaches, the occurrence of multiple tumours, tumour size or sarcoma-like histological features. HIV-SMT had the poorest overall survival, which might be attributed to HIV-associated infectious complications. PMID:25027306

Hussein, Kais; Rath, Berenice; Ludewig, Britta; Kreipe, Hans; Jonigk, Danny

2014-09-01

277

Rare oesophageal tumours: experience of one centre.  

PubMed

AIM OF STUDY: The aim of this study is to compare demographic and clinical data as well as applied treatment methods in patients with rare benign and malignant tumours of the oesophagus. METHODS: Eight hundred and thirty patients with oesophageal cancer were treated in the Department of Surgical Oncology in 1960-2005. In 15 cases (1.8 %), rare benign (n?=?11) or malignant (n?=?4) types of tumours were diagnosed. Patients with rare oesophageal tumours were included in the study, excluding those with squamous cell carcinoma or adenocarcinoma of the oesophagus. Demographic and clinical data were analysed from each patient qualified for the study. Oesophageal X-rays with contrast medium, gastroscopies and, as of 1991, computed tomographies (CTs) were performed as preoperative diagnostic procedures. RESULTS: In the postoperative histopathological examinations, all benign tumours proved to be oesophageal leiomyomas. Four different malignant tumours-a sarcoma, a neuroendocrine carcinoma, a lymphoma, and a squamous cell carcinoma in a patient with Crohn's disease, were diagnosed in the other four patients. In a group of 15 patients with rare oesophageal tumours there were ten (66.7 %) males and five (33.3 %) females. In patients with benign and malignant tumours, the mean age for the benign group reached 44 years (range: 26-75 years old) and 54.7 years (range: 47-59 years old) for the malignant group. In the preoperative period, symptoms such as swallowing disturbances, retrosternal pains, and epigastric pains were observed. Dysphagia was the leading symptom in patients with benign and malignant oesophageal tumours. Out of 15 patients, surgical procedure was carried out in 13 cases with rare oesophageal tumours. In the group of 11 patients, with benign tumours, ten (90.2 %) warranted surgical treatment. Three patients (75 %) with malignant oesophageal tumours underwent an extensive Akiyama procedure of oesophageal resection. Chemo- and radiotherapy alone were performed on one (25 %) patient with oesophageal lymphoma. Postoperative complications were observed in only four (26.6 %) patients; pneumonia in the postoperative period was diagnosed in two patients who underwent surgery; infections of the postoperative wounds were diagnosed in the other two patients. CONCLUSIONS: Benign oesophageal tumours are characterised by similar clinical symptoms to malignant tumours of this organ. It is more complicated to obtain biopsy specimens for a histopathological examination in cases of benign tumours in comparison to malignant tumours. Treatment methods should be adjusted individually for each patient with a rare oesophageal tumour. For rare benign oesophageal tumours, the results of treatment are very good; however, for malignant tumours the prognosis depends on their histopathological type. PMID:23440953

Zielinski, J; Kruszewski, W J; Jaworski, R; Haponiuk, I; Irga, N; Zygon, J; Kopacz, A; Jaskiewicz, J

2012-12-01

278

Gastric and duodenal neuroendocrine tumours.  

PubMed

Gastric neuroendocrine neoplasms (NENs) are increasing in frequency and have a varied spectrum with regard to histology, clinicopathologic background, stage, and prognosis. They are usually discovered incidentally, are for the most part benign and are associated with hypergastrinaemia (secondary either to chronic atrophic gastritis or rarely Zollinger-Ellison syndrome; types 1 and 2, respectively) or more rarely sporadic type 3. Applications of recent staging and grading systems - namely using Ki-67 proliferative indices - (from ENETS and WHO 2010) can be particularly helpful in further categorising these tumours. The natural history of Type 1 gastric carcinoids is generally (>95%) favourable and simple surveillance is usually recommended for small (<1 cm) T1 tumours, with local (endoscopic or surgical) resection for larger lesions. Other potential therapies such as somatostatin analogues and gastrin receptor antagonists may offer newer therapeutic possibilities. Rarely, gastric NENs have a malignant course and this is usually confined to Type 2 and especially Type 3 tumours; the latter mimic the biological course of gastric adenocarcinoma and require radical oncological therapies. Most duodenal NENs, apart from gastrinomas (that are not dealt with here) are sporadic and non functional. They are also increasing in frequency probably due to incidental discovery at endoscopy or imaging for other reasons and this may account for their overall good prognosis. Peri-ampullary and ampullary NENs may have a more aggressive outcome and should be carefully appraised and treated (often with surgical resection). PMID:23582915

O'Toole, Dermot; Delle Fave, Gianfranco; Jensen, Robert T

2012-12-01

279

Classification accuracy of serum Apo A-I and S100B for the diagnosis of mild traumatic brain injury and prediction of abnormal initial head computed tomography scan.  

PubMed

The objective of the current study was to determine the classification accuracy of serum S100B and apolipoprotein (apoA-I) for mild traumatic brain injury (mTBI) and abnormal initial head computed tomography (CT) scan, and to identify ethnic, racial, age, and sex variation in classification accuracy. We performed a prospective, multi-centered study of 787 patients with mTBI who presented to the emergency department within 6 h of injury and 467 controls who presented to the outpatient laboratory for routine blood work. Serum was analyzed for S100B and apoA-I. The outcomes were disease status (mTBI or control) and initial head CT scan. At cutoff values defined by 90% of controls, the specificity for mTBI using S100B (0.899 [95% confidence interval (CI): 0.78-0.92]) was similar to that using apoA-I (0.902 [0.87-0.93]), and the sensitivity using S100B (0.252 [0.22-0.28]) was similar to that using apoA-I (0.249 [0.22-0.28]). The area under the receiver operating characteristic curve (AUC) for the combination of S100B and apoA-I (0.738, 95% CI: 0.71, 0.77), however, was significantly higher than the AUC for S100B alone (0.709, 95% CI: 0.68, 0.74, p=0.001) and higher than the AUC for apoA-I alone (0.645, 95% CI: 0.61, 0.68, p<0.0001). The AUC for prediction of abnormal initial head CT scan using S100B was 0.694 (95%CI: 0.62, 0.77) and not significant for apoA-I. At a S100B cutoff of <0.060 ?g/L, the sensitivity for abnormal head CT was 98%, and 22.9% of CT scans could have been avoided. There was significant age and race-related variation in the accuracy of S100B for the diagnosis of mTBI. The combined use of serum S100B and apoA-I maximizes classification accuracy for mTBI, but only S100B is needed to classify abnormal head CT scan. Because of significant subgroup variation in classification accuracy, age and race need to be considered when using S100B to classify subjects for mTBI. PMID:23758329

Bazarian, Jeffrey J; Blyth, Brian J; He, Hua; Mookerjee, Sohug; Jones, Courtney; Kiechle, Karin; Moynihan, Ryan; Wojcik, Susan M; Grant, William D; Secreti, LaLainia M; Triner, Wayne; Moscati, Ronald; Leinhart, August; Ellis, George L; Khan, Jawwad

2013-10-15

280

Classification Accuracy of Serum Apo A-I and S100B for the Diagnosis of Mild Traumatic Brain Injury and Prediction of Abnormal Initial Head Computed Tomography Scan  

PubMed Central

Abstract The objective of the current study was to determine the classification accuracy of serum S100B and apolipoprotein (apoA-I) for mild traumatic brain injury (mTBI) and abnormal initial head computed tomography (CT) scan, and to identify ethnic, racial, age, and sex variation in classification accuracy. We performed a prospective, multi-centered study of 787 patients with mTBI who presented to the emergency department within 6?h of injury and 467 controls who presented to the outpatient laboratory for routine blood work. Serum was analyzed for S100B and apoA-I. The outcomes were disease status (mTBI or control) and initial head CT scan. At cutoff values defined by 90% of controls, the specificity for mTBI using S100B (0.899 [95% confidence interval (CI): 0.78–0.92]) was similar to that using apoA-I (0.902 [0.87–0.93]), and the sensitivity using S100B (0.252 [0.22–0.28]) was similar to that using apoA-I (0.249 [0.22–0.28]). The area under the receiver operating characteristic curve (AUC) for the combination of S100B and apoA-I (0.738, 95% CI: 0.71, 0.77), however, was significantly higher than the AUC for S100B alone (0.709, 95% CI: 0.68, 0.74, p=0.001) and higher than the AUC for apoA-I alone (0.645, 95% CI: 0.61, 0.68, p<0.0001). The AUC for prediction of abnormal initial head CT scan using S100B was 0.694 (95%CI: 0.62, 0.77) and not significant for apoA-I. At a S100B cutoff of <0.060??g/L, the sensitivity for abnormal head CT was 98%, and 22.9% of CT scans could have been avoided. There was significant age and race-related variation in the accuracy of S100B for the diagnosis of mTBI. The combined use of serum S100B and apoA-I maximizes classification accuracy for mTBI, but only S100B is needed to classify abnormal head CT scan. Because of significant subgroup variation in classification accuracy, age and race need to be considered when using S100B to classify subjects for mTBI. PMID:23758329

Blyth, Brian J.; He, Hua; Mookerjee, Sohug; Jones, Courtney; Kiechle, Karin; Moynihan, Ryan; Wojcik, Susan M.; Grant, William D.; Secreti, LaLainia M.; Triner, Wayne; Moscati, Ronald; Leinhart, August; Ellis, George L.; Khan, Jawwad

2013-01-01

281

Skin adnexal neoplasms—part 2: An approach to tumours of cutaneous sweat glands  

PubMed Central

Tumours of cutaneous sweat glands are uncommon, with a wide histological spectrum, complex classification and many different terms often used to describe the same tumour. Furthermore, many eccrine/apocrine lesions coexist within hamartomas or within lesions with composite/mixed differentiation. In addition to the eccrine and apocrine glands, two other skin sweat glands have recently been described: the apoeccrine and the mammary?like glands of the anogenital area. In this review (the second of two articles on skin adnexal neoplasms), common as well as important benign and malignant lesions of cutaneous sweat glands are described, and a summary for differentiating primary adnexal neoplasms from metastatic carcinoma is outlined, striving to maintain a common and acceptable terminology in this complex subject. Composite/mixed adnexal tumours are also discussed briefly. PMID:16882695

Obaidat, Nidal A; Alsaad, Khaled O; Ghazarian, Danny

2007-01-01

282

Modelling of tumour repopulation after chemotherapy  

Microsoft Academic Search

While repopulation is a clinically observed phenomenon after radiotherapy, repopulation of tumour cells between cycles of\\u000a chemotherapy is usually a neglected factor in cancer treatment. As the effect of both radiotherapy and chemotherapy on tumour\\u000a cells is the same (attack on cancer cells), the response of the tumour to injury and cell loss from the two treatment methods\\u000a should be

Loredana Marcu; Eva Bezak

2010-01-01

283

Imaging of testicular germ cell tumours  

PubMed Central

In testicular germ cell tumour (GCT), imaging plays a central role in assessment of tumour bulk, sites of metastases, monitoring response to therapy, surgical planning and accurate assessment of disease at relapse. The primary modality used for imaging patients with GCT is computed tomography (CT) but plain film radiography, ultrasound, magnetic resonance imaging (MRI) and positron emission tomography (PET) may all have roles to play. This article reviews the role of imaging of testicular germ cell tumours. PMID:16966068

Dalal, P U; Sohaib, S A; Huddart, R

2006-01-01

284

[Epidemiology of brain metastases].  

PubMed

The most frequent intracranial brain tumours are brain metastases. All types of cancer can develop brain metastases but two thirds of brain metastases occurring in adult patients are secondary to one of these three cancers: lung cancer, breast cancer and melanoma. In accordance with these data, this review is focusing on the epidemiology of these three types of cancer. We report here the incidence, risk factors, median time of brain metastases occurrence after diagnosis of the primary cancer, prognosis and median survival for these three types of cancer. We also discuss the clinical implications of these data. The second part of this review is focusing on the Graded Prognostic Assessment scores in all types of primary cancer with brain metastases, how they can be applied in clinical research for a better stratification of patients, and to some extent in clinical practice to guide decisions for personalized treatments. These scores provide a better understanding of the different profiles of clinical evolution that can be observed amongst patients suffering from brain metastases according to the type of primary cancer. We highlighted the most remarkable and useful clinical implications of these data. PMID:25636729

Taillibert, S; Le Rhun, É

2015-02-01

285

[National network of paediatric central nervous system tumours reviewing by the Groupe d'Étude de Neuropathologie Oncologique Pediatrique (GENOP)].  

PubMed

Diagnosis of paediatric tumours of the central nervous system is often difficult because WHO classification criteria are mainly defined for adults tumours and do not always apply to their paediatric counterparts. These tumours are rare (400 cases/year among more than 50 pathological subtypes per year in France). Pathological diagnosis may be a challenge for a general pathologist with a too low number of paediatric cases in his recruitment. Hence, a reference group of paediatric neuropathologists was formed (GENOP) on the behalf of the comité "Tumeurs Cérébrales" de la Société Française de lutte contre les Cancers de l'Enfant. This network is supported by the Institut National du Cancer (INCa). GENOP aim is to structure a centralised review of paediatric central nervous system tumours in order to harmonise neuropathological diagnosis at the national level and enhance patients care. Cases assessed during the last 3 years led GENOP to better identify tumours subtypes for which there is a diagnostic challenge. A set of immunohistochemical or molecular specialised techniques was developed, leading to an increased diagnostic accuracy. It allowed a better distinction between diffuse and circumscribed glioma, a better recognition of glioneuronal differentiation and a better subtyping of embryonal tumours such as medulloblastomas. Inter-observer agreement varied according to the tumour subtypes. PMID:24630640

Meyronet, David; Silva, Karen; Figarella-Branger, Dominique; Godfraind, Catherine; Delisle, Marie-Bernadette; Maurage, Claude-Alain; Miquel, Catherine; Varlet, Pascale; Gentet, Jean-Claude; Salamon, Anne-Isabelle-Bertozzi; Vasiljevic, Alexandre; Jouvet, Anne

2014-02-01

286

Resveratrol, a Natural Product Present in Wine, Decreases Tumour Growth in a Rat Tumour Model  

Microsoft Academic Search

Resveratrol administration to rats inoculated with a fast growing tumour (the Yoshida AH-130 ascites hepatoma) caused a very significant decrease (25%) in the tumour cell content. The effects of this diphenol were associated with an increase in the number of cells in the G2\\/M cell cycle phase. Interestingly, flow cytometric analysis of the tumour cell population revealed the existence of

Neus Carbó; Paola Costelli; Francesco M. Baccino; Francisco J. López-Soriano; Josep M. Argilés

1999-01-01

287

Leaf Classification  

NSDL National Science Digital Library

In this activity, students learn about hierarchical classification systems and create their own classification system for leaves they collect in the field. They learn about the key characteristics for classification systems and see that there are multiple ways to classify objects. This is a learning activity associated with the GLOBE land cover/biology investigations and is supported by the Land Cover/Biology chapter of the GLOBE Teacher's Guide.

2012-08-03

288

Immunology of naturally transmissible tumours  

E-print Network

), while the most recent estimate predicts emergence between 10 000 and 12 000 years ago (6). Devil Facial Tumour Disease The Tasmanian devil is a marsupial carnivore endemic to the island of Tasmania. The species suffered population reductions... with the arrival of European settlers to Tasmania, but over time the population recovered, with an estimated 130 000 to 150 000 devils in Tasmania in the early 1990’s (8). Between 1996 and 2001 devils were identified across the east coast of Tasmania with large...

Siddle, Hannah V.; Kaufman, Jim

2014-09-04

289

Gastrointestinal Stromal Tumours: An Update  

PubMed Central

Purpose. To study the evolution of concepts concerning gastrointestinal stromal tumours (GISTs) over 30 years. Discussion. GISTs have been, for more than 30 years, the subject of considerable controversy regarding their line of differentiation as well as the prediction of their behaviour. Furthermore, once they spread within the peritoneal cavity, they are extremely hard to control. The recent findings of c-Kit mutations and the immunohistochemical detection of the product of this gene, KIT or CD117, in the mainly non-myogenic subset of this family of tumours, has led to a reappraisal of this group of lesions, which, with some exceptions, is now thought to be derived from the interstitial cells of Cajal, and this has facilitated a clearer definition of their pathological spectrum. In this article, we review chronologically the evolution of the concept of GIST with the gradual application of electron microscopy, immunohistochemistry, DNA ploidy analysis. We discuss the impact of these techniques on the pathological assessment and clinical management of GISTs. PMID:18521245

Somerhausen, Nicolas De Saint Aubain

1998-01-01

290

[Identification and characteristics of concanavalin A-binding neurospecific glycoproteins in human brain and brain tumors].  

PubMed

Soluble and membrane-bound neurospecific Con A-binding glycoproteins from human brain and tumours were identified and characterized, using a procedure which included stepwise extraction with low and high ionic strength buffers, buffered. Triton X-100 and sodium deoxycholate followed by ConA-Sepharose column chromatography, SDS-PAAG electrophoresis and immunoblotting. Adsorbed antisera against different types of neurospecific glycoproteins were used. The bulk of neurospecific glycoproteins (11 and 13) were revealed in protein fractions extracted with low ionic strength buffers and Triton X-100. In astrocytomas and glyoblastomas, some neurospecific glycoproteins were absent. Some glycoproteins were found in tumours, but were absent in brain tissue. Soluble, 77 kD glycoprotein, 11 and 16 kD glycoproteins solubilized with high ionic strength buffers and intrinsic membrane-bound 51, 57, 61, 74 and 77 kD glycoproteins can be viewed as stable neurospecific markers in malignant brain tumours. PMID:3233229

Berezin, V A; Shevchenko, G M; Ga?dar, L I; Zuban', T I; Azarkina, V V

1988-10-01

291

Tumour resistance to cisplatin: a modelling approach  

Microsoft Academic Search

Although chemotherapy has revolutionized the treatment of haematological tumours, in many common solid tumours the success has been limited. Some of the reasons for the limitations are: the timing of drug delivery, resistance to the drug, repopulation between cycles of chemotherapy and the lack of complete understanding of the pharmacokinetics and pharmacodynamics of a specific agent. Cisplatin is among the

L. Marcu; E. Bezak; I. Olver; T. van Doorn

2005-01-01

292

Cerebrospinal fluid rhinorrhoea in pituitary tumours1  

PubMed Central

Three cases of CSF rhinorrhoea due to pituitary tumours are reported and the literature reviewed. The treatment of choice appears to be trans-sphenoidal exploration of the pituitary fossa with insertion of a free muscle graft followed by radiotherapy. The probability of the tumour being a prolactin-secreting adenoma is discussed. PMID:7017123

Cole, I E; Keene, Malcolm

1980-01-01

293

[Single-cell sequencing and tumour heterogeneity].  

PubMed

The heterogeneity of tumours is now beginning to be documented precisely by single-cell new-generation sequencing. Recently published results on breast tumours show that each of the cells analysed displays a unique pattern of point mutations. This extensive genetic diversity is present before any treatment, and is likely to cause resistance to initially successful targeted therapies. PMID:25537050

Jordan, Bertrand

2014-12-01

294

Small bowel tumours: yield of enteroscopy  

Microsoft Academic Search

A total of 258 patients with obscure gastrointestinal bleeding were referred for small bowel enteroscopy, a procedure which allows endoscopic evaluation of most of the small intestine. A small bowel tumour was found in 5% of patients. In 50% of patients no diagnosis could be made, but when the cause of obscure bleeding was discovered small bowel tumours were the

B S Lewis; A Kornbluth; J D Waye

1991-01-01

295

Postchemoembolisation syndrome – tumour necrosis or hepatocyte injury?  

Microsoft Academic Search

Transarterial chemoembolisation of liver tumours is typically followed by elevated body temperature and liver transaminase enzymes. This has often been considered to indicate successful embolisation. The present study questions whether this syndrome reflects damage to tumour cells or to the normal hepatic tissue. The responses to 256 embolisations undertaken in 145 patients subdivided into those with hepatocyte-derived (primary hepatocellular carcinoma)

S J Wigmore; D N Redhead; B N J Thomson; E J Currie; R W Parks; K K Madhavan; O J Garden

2003-01-01

296

Fingerprint classification  

Microsoft Academic Search

A fingerprint classification algorithm is presented in this paper. Fingerprints are classified into five categories: arch, tented arch, left loop, right loop and whorl. The algorithm extracts singular points (cores and deltas) in a fingerprint image and performs classification based on the number and locations of the detected singular points. The classifier is invariant to rotation, translation and small amounts

Kalle Karu; Anil K. Jain

1996-01-01

297

Hubble Classification  

Microsoft Academic Search

A classification scheme for galaxies, devised in its original form in 1925 by Edwin P Hubble (1889-1953), and still widely used today. The Hubble classification recognizes four principal types of galaxy---elliptical, spiral, barred spiral and irregular---and arranges these in a sequence that is called the tuning-fork diagram....

P. Murdin

2000-01-01

298

Spectral classification  

Microsoft Academic Search

Taxonomic classification of astronomically observed stellar objects is described in terms of spectral properties. Stars receive a classification containing a letter, number, and a Roman numeral, which relates the star to other stars of higher or lower Roman numerals. The citation indicates the stellar chromatic emission in relation to the wavelengths of other stars. Standards are chosen from the available

C. Jaschek

1982-01-01

299

Hubble Classification  

NASA Astrophysics Data System (ADS)

A classification scheme for galaxies, devised in its original form in 1925 by Edwin P Hubble (1889-1953), and still widely used today. The Hubble classification recognizes four principal types of galaxy—elliptical, spiral, barred spiral and irregular—and arranges these in a sequence that is called the tuning-fork diagram....

Murdin, P.

2000-11-01

300

Neuroblastoma tumour genetics: clinical and biological aspects  

PubMed Central

Neuroblastoma tumour cells show complex combinations of acquired genetic aberrations, including ploidy changes, deletions of chromosome arms 1p and 11q, amplification of the MYCN oncogene, and—most frequently—gains of chromosome arm 17q. Despite intensive investigation, the fundamental role of these features in neuroblastoma initiation and progression remains to be understood. Nonetheless, great progress has been made in relating tumour genetic abnormalities to tumour behaviour and to clinical outcome; indeed, neuroblastoma provides a paradigm for the clinical importance of tumour genetic abnormalities. Knowledge of MYCN status is increasingly being used in treatment decisions for individual children, and the clinical value of 1p and 17q data as adjuncts or refinements in risk stratification is under active investigation. Reliable detection of these molecular cytogenetic features should be regarded as mandatory for all new cases at presentation. Key Words: neuroblastoma genetics • 17q gain in neuroblastoma • neuroblastoma: 1p and MYCN • tumour genetics and prognosis PMID:11729208

Bown, N

2001-01-01

301

Canine transmissible venereal tumour: a review.  

PubMed

Canine transmissible venereal tumour (CTVT) is a contagious venereal tumour of dogs, commonly observed in dogs that are in close contact with one another, or in stray and wild dogs that exhibit unrestrained sexual activity. CTVT represents a unique, naturally transmissible, contagious tumour, where the mutated tumour cell itself is the causative agent and perpetuates as a parasitic allograft in the host. Clinical history, signalment and cytological features are often obvious for establishing a diagnosis though biopsy and histological examination may be needed in atypical cases. Most cases are curable with three intravenous injections of vincristine sulphate at weekly intervals. The role of stray and wild dogs makes the disease difficult to control and necessitates sustained animal birth control in stray dogs along with prompt therapy of the affected dogs. This review captures the manifold developments in different areas embracing this fascinating tumour, including its biology, diagnosis and therapeutic alternatives. PMID:23981098

Ganguly, B; Das, U; Das, A K

2013-08-25

302

Giant Malignant Phyllodes Tumour of Breast  

PubMed Central

The term phyllodes tumour includes lesions ranging from completely benign tumours to malignant sarcomas. Clinically phyllodes tumours are smooth, rounded, and usually painless multinodular lesions indistinguishable from fibroadenomas. Percentage of phyllodes tumour classified as malignant ranges from 23% to 50%. We report a case of second largest phyllodes tumour in a 35-year-old lady who presented with swelling of right breast since 6 months, initially small in size, that progressed gradually to present size. Examination revealed mass in the right breast measuring 36×32?cms with lobulated firm surface and weighing 10?kgs. Fine needle aspiration cytology was reported as borderline phyllodes; however core biopsy examination showed biphasic neoplasm with malignant stromal component. Simple mastectomy was done and specimen was sent for histopathological examination which confirmed the core biopsy report. Postoperatively the patient received chemotherapy and radiotherapy. The patient is on follow-up for a year and has not shown any evidence of metastasis or recurrence. PMID:25548696

Krishnamoorthy, Ramakrishnan; Savasere, Thejas; Prabhuswamy, Vinod Kumar; Babu, Rajashekhara; Shivaswamy, Sadashivaiah

2014-01-01

303

Application of Data Mining Techniques for Medical Image Classification  

Microsoft Academic Search

Breast cancer represents the second leading cause of cancer deaths in women today and it is the most common type of cancer in women. This paper presents some experiments for tumour detection in digital mammography. We inves- tigate the use of different data mining techniques, neural networks and association rule mining, for anomaly detec- tion and classification. The results show

Maria-luiza Antonie; Osmar R. Zaïane; Alexandru Coman

2001-01-01

304

Neutron medical treatment of tumours — a survey of facilities  

NASA Astrophysics Data System (ADS)

Neutron therapy has two branches: Fast Neutron Therapy (FNT) and Boron Neutron Capture Therapy (BNCT). The mean neutron energies used for FNT range from 2 MeV to 25 MeV whereas the maximum energy for BNCT is about 10 keV. Neutron generators for FNT have been cyclotrons, accelerators and reactors, whereas BNCT is so far bound to reactors. Both therapies use the effects of high-LET radiation (secondary recoil protons and alpha particles, respectively) and can attack otherwise radioresistant tumours, however, with the hazard of adverse effects for irradiated healthy tissue. FNT has been administered to about 30,000 patients world-wide. From formerly 40 facilities, only eight are operational or stand-by today. The reasons for this development have been, on the one hand, related to technical and economical conditions; on the other hand, strong side effects and insufficient proof of clinical results in the early years as well as increasing competition with new clinical methods have reduced patient numbers. In fact, strict observations of indications, appropriate therapy-planning including low-LET radiation, and consequent treatment of side effects have lead to remarkable results in the meantime. BNCT initially was developed for the treatment of extremely aggressive forms of brain tumour, taking advantage of the action of the blood-brain-barrier which allows for a boronated compound to be selectively enriched in tumour cells. Meanwhile, also malignant melanoma (MM) and Head-and-Neck (H&T) tumours are treated because of their relative radioresistance. At present, epithermal beams with sufficient flux are available only at two facilities. Existing research reactors were indispensable in the development of BNCT, but are to be replaced by hospital-based epithermal neutron sources. Clinical results indicate significantly increased survival times, but the number of patients ever treated is still below 1,000. 3D-dose calculation systems have been developed at several facilities and guarantee a high safety for both therapies, FNT and BNCT.

Wagner, F. M.; Loeper-Kabasakal, B.; Breitkreutz, H.

2012-03-01

305

Reaching a Moveable Visual Target: Dissociations in Brain Tumour Patients  

ERIC Educational Resources Information Center

Damage to the posterior parietal cortex (PPC) can lead to Optic Ataxia (OA), in which patients misreach to peripheral targets. Recent research suggested that the PPC might be involved not only in simple reaching tasks toward peripheral targets, but also in changing the hand movement trajectory in real time if the target moves. The present study…

Buiatti, Tania; Skrap, Miran; Shallice, Tim

2013-01-01

306

Lactoferrin induced neuronal differentiation: A boon for brain tumours.  

PubMed

The cumulative treatments of bovine lactoferrin (bLf) and iron saturated lactoferrin (Fe-bLf) in the neuroblastoma cells showed neuronal differentiating actions evident with the expression of specific differentiating markers, ?-tubulin III and neurofilaments. The protein treatments also showed lowered endogenous survivin that is responsible for cell proliferation and the miRNA 584 and miRNA214-3p, required for differentiation. Further, bLf adopted the PI3K signalling predominantly, while Fe-bLf involved both the PI3K and ERK signalling for inducing differentiation. In conclusion, this is the first study to report the neuronal differentiating effects of milk proteins and future studies are warranted for clinical application. PMID:25498991

Sriramoju, Bhasker; Kanwar, Rupinder K; Kanwar, Jagat R

2015-04-01

307

[Cartilage tumours of the bone. Diagnosis and therapy].  

PubMed

Primary malignant bone tumours are rare. The annual incidence of these tumours is 10 per 1 million. Nearly 30% of the primary malignant bone tumours are malignant cartilage tumours. The frequency of benign cartilage tumours cannot be definitely estimated because these tumours are normally clinically inapparent and therefore often diagnosed as an incidental finding. The cartilage tumours appear as benign lesions (e.g. chondroma), as borderline tumours (proliferative chondroma vs grade I chondrosarcoma) or as highly malignant chondrosarcoma (e.g. dedifferentiated chondrosarcoma). Commensurate with the different clinical and oncological manifestations of the cartilage tumours, there are wide differences in the treatment and clinical course of the individual tumour. This article discusses the problems in the diagnosis and treatment of cartilage tumours from an orthopaedic point of view. PMID:16865383

Streitbuerger, A; Hardes, J; Gebert, C; Ahrens, H; Winkelmann, W; Gosheger, G

2006-08-01

308

Low-level and high-level modulations of fixational saccades and high frequency oscillatory brain activity in a visual object classification task  

PubMed Central

Until recently induced gamma-band activity (GBA) was considered a neural marker of cortical object representation. However, induced GBA in the electroencephalogram (EEG) is susceptible to artifacts caused by miniature fixational saccades. Recent studies have demonstrated that fixational saccades also reflect high-level representational processes. Do high-level as opposed to low-level factors influence fixational saccades? What is the effect of these factors on artifact-free GBA? To investigate this, we conducted separate eye tracking and EEG experiments using identical designs. Participants classified line drawings as objects or non-objects. To introduce low-level differences, contours were defined along different directions in cardinal color space: S-cone-isolating, intermediate isoluminant, or a full-color stimulus, the latter containing an additional achromatic component. Prior to the classification task, object discrimination thresholds were measured and stimuli were scaled to matching suprathreshold levels for each participant. In both experiments, behavioral performance was best for full-color stimuli and worst for S-cone isolating stimuli. Saccade rates 200–700 ms after stimulus onset were modulated independently by low and high-level factors, being higher for full-color stimuli than for S-cone isolating stimuli and higher for objects. Low-amplitude evoked GBA and total GBA were observed in very few conditions, showing that paradigms with isoluminant stimuli may not be ideal for eliciting such responses. We conclude that cortical loops involved in the processing of objects are preferentially excited by stimuli that contain achromatic information. Their activation can lead to relatively early exploratory eye movements even for foveally-presented stimuli. PMID:24391611

Kosilo, Maciej; Wuerger, Sophie M.; Craddock, Matt; Jennings, Ben J.; Hunt, Amelia R.; Martinovic, Jasna

2013-01-01

309

Sampled sinusoidal stimulation profile and multichannel fuzzy logic classification for monitor-based phase-coded SSVEP brain-computer interfacing  

NASA Astrophysics Data System (ADS)

Objective. The performance and usability of brain-computer interfaces (BCIs) can be improved by new paradigms, stimulation methods, decoding strategies, sensor technology etc. In this study we introduce new stimulation and decoding methods for electroencephalogram (EEG)-based BCIs that have targets flickering at the same frequency but with different phases. Approach. The phase information is estimated from the EEG data, and used for target command decoding. All visual stimulation is done on a conventional (60-Hz) LCD screen. Instead of the ‘on/off’ visual stimulation, commonly used in phase-coded BCI, we propose one based on a sampled sinusoidal intensity profile. In order to fully exploit the circular nature of the evoked phase response, we introduce a filter feature selection procedure based on circular statistics and propose a fuzzy logic classifier designed to cope with circular information from multiple channels jointly. Main results. We show that the proposed visual stimulation enables us not only to encode more commands under the same conditions, but also to obtain EEG responses with a more stable phase. We also demonstrate that the proposed decoding approach outperforms existing ones, especially for the short time windows used. Significance. The work presented here shows how to overcome some of the limitations of screen-based visual stimulation. The superiority of the proposed decoding approach demonstrates the importance of preserving the circularity of the data during the decoding stage.

Manyakov, Nikolay V.; Chumerin, Nikolay; Robben, Arne; Combaz, Adrien; van Vliet, Marijn; Van Hulle, Marc M.

2013-06-01

310

October 24 - 25, 2005:MR Spectroscopic Analysis of Tumour Metabolic Phenotype Changes in Response to Therapy, Risto A. Kauppinen  

Cancer.gov

MR Spectroscopic Analysis of Tumour Metabolic Phenotype Changes in Response to Therapy Risto A. Kauppinen University of Birmingham U.K. R.A.Kauppinen@bham.ac.uk 2 NAA Cr Cho Cr Glx Tau Myo-ins Glx/NAA Myo-ins MM/ Lip/ Lac 2 PPM 3 4 1 0 5 Rat brain LASER TR

311

Malignant tumours of the small intestine.  

PubMed

Adenocarcinoma, neuroendocrine tumours, sarcomas and lymphomas are the four most common malignant tumours arising in the small intestine, although over forty different histological subtypes are described. Collectively these account for only 2% of cancers of the digestive system. The incidence of small bowel cancer has increased in recent decades with a four-fold increase in carcinoid tumours. Risk factors for small bowel tumours include coeliac disease, inflammatory bowel disease and a number of genetic abnormalities. The non-specific nature of their symptoms and the difficulty in visualising these tumours with normal endoscopic techniques often results in late diagnosis. Furthermore the paucity of literature on this topic has made it difficult to standardise management. There has however been marked improvement in imaging methods resulting in earlier diagnosis in many cases. As expected, early detection of localised, well differentiated tumours followed by surgical resection with negative margins offers the best chance of long term survival. Better adjuvant treatment, notably for gastrointestinal stromal tumours, has improved 5-year survival rates significantly. Development of surveillance guidelines for at risk populations may be a valuable way of improving early diagnosis of this challenging group of conditions. PMID:24637026

Reynolds, Ian; Healy, Paul; Mcnamara, Deborah A

2014-10-01

312

Brain herniation  

MedlinePLUS

... herniation; Uncal herniation; Subfalcine herniation; Tonsillar herniation; Herniation - brain ... Brain herniation occurs when something inside the skull produces pressure that moves brain tissues. This is most ...

313

Endothelial cell KIT expression in human tumours.  

PubMed

Receptor tyrosine kinases expressed in endothelial cells are potential targets for therapy with specific tyrosine kinase inhibitors. Endothelial cell KIT expression has not been systematically evaluated in human cancer. In the present study, endothelial cell KIT expression was assessed in 345 tumours consisting of 34 different histological types using a tissue microarray technique. Marked KIT expression occurred in the tumour endothelial cells only in primary glioblastomas in the microarray. Moderate to strong KIT and phosphorylated KIT expression was detected in the tumour endothelial cells in six (16%) and seven (19%) of the 37 primary glioblastomas examined, respectively. In whole tissue sections, KIT and phosphorylated KIT were expressed in tumour endothelial cells in 13 (59%) and 11 (50%) of the 22 glioblastomas examined, respectively. RNA in situ hybridization showed KIT mRNA expression in most glioblastomas both in tumour vessel endothelial cells and in perinecrotic palisading glioblastoma cells, whereas little KIT mRNA was found in the endothelial cells of colon or pancreatic carcinomas. Phosphorylated KIT, its ligand stem cell factor, and the downstream signalling molecules phosphorylated Akt and mTOR were often expressed in glioblastoma cells located in the perinecrotic tumour areas that often also contained abundant HIF-1alpha. It is concluded that marked KIT and phosphorylated KIT expression is frequently present in the endothelial cells of glioblastomas, which are known to harbour florid microvascular proliferation with characteristic morphological features. Glioblastomas also express phosphorylated KIT and its activated downstream signalling molecules in the tumour cells. Lower levels of KIT and phosphorylated KIT are present in endothelial cells of other tumour types and in normal tissues. Endothelial cell and tumour cell expression of activated KIT might explain in part the responsiveness of glioblastomas to the combination of imatinib (an inhibitor of KIT) and hydroxyurea. PMID:17294421

Sihto, H; Tynninen, O; Bützow, R; Saarialho-Kere, U; Joensuu, H

2007-03-01

314

Askin's tumour in pregnancy with dismal prognosis.  

PubMed

Askin's tumour is a rare malignant neoplasm of the chest wall. A 23-year-old primigravida patient was admitted to the hospital with complaints of chest wall swelling, cough and dyspnoea. Radiological examination showed a chest wall mass in right hemithorax with erosion of ribs and moderate pleural effusion. Fine-needle aspiration cytology was suggestive of malignant small round cell tumour. Immunohistochemical analysis together with the clinical and radiological findings led to the definitive diagnosis of Askin's tumour. Despite receiving multimodality therapy, she had residual soft tissue mass and died after 6 months. Rarity of this malignancy during pregnancy renders the case unique. PMID:25354014

Sidhu, Kiranjit; Kashyap, Surender; Negi, R S; Solanki, Anjali

2014-10-29

315

Photodynamic therapy and anti-tumour immunity  

PubMed Central

Photodynamic therapy (PDT) uses non-toxic photosensitizers and harmless visible light in combination with oxygen to produce cytotoxic reactive oxygen species that kill malignant cells by apoptosis and/or necrosis, shut down the tumour microvasculature and stimulate the host immune system. In contrast to surgery, radiotherapy and chemotherapy that are mostly immunosuppressive, PDT causes acute inflammation, expression of heat-shock proteins, invasion and infiltration of the tumour by leukocytes, and might increase the presentation of tumour-derived antigens to T cells. PMID:16794636

Castano, Ana P.; Mroz, Pawel; Hamblin, Michael R.

2010-01-01

316

Jaw and gum tumours in children  

Microsoft Academic Search

Introduction  Jaw and gum tumours are rare conditions in children. Children presenting with jaw tumours during 2001 till 2007 are presented.\\u000a Their modes of presentation, operative procedures and findings, histology and post operative results have been described.\\u000a \\u000a \\u000a \\u000a Materials and methods  Fourteen children presenting with jaw and gum tumours are retrospectively analysed. Acute inflammatory and developmental cyst\\u000a are excluded from the study. Relevant

Hemonta Kumar Dutta

2009-01-01

317

Radiopharmaceuticals as probes to characterize tumour tissue.  

PubMed

Tumour cells exhibit several properties that allow them to grow and divide. A number of these properties are detectable by nuclear imaging methods. We discuss crucial tumour properties that can be described by current radioprobe technologies, further discuss areas of emerging radioprobe development, and finally articulate need areas that our field should aspire to develop. The review focuses largely on positron emission tomography and draws upon the seminal 'Hallmarks of Cancer' review article by Hanahan and Weinberg in 2011 placing into context the present and future roles of radiotracer imaging in characterizing tumours. PMID:25647074

Alam, Israt S; Arshad, Mubarik A; Nguyen, Quang-Dé; Aboagye, Eric O

2015-04-01

318

Mineral Classification  

NSDL National Science Digital Library

This problem set challenges students to determine the chemical classification of minerals based on their chemical formula (provided). For oxygen-bearing minerals, students must also provide the valences of the various cations.

319

Herbicide Classification  

NSDL National Science Digital Library

This lesson focuses on understanding the classification system intowhich herbicides are organized. Terms of classification, classificationhierachy, examples of classification and a brief overview of the eightmodes of action are all discussed in this lesson. Once this isunderstood it is much easier to grasp similar herbicides and know whythey may exhibit certain symptoms to weeds and plants alike.Objectives:1.Understand how herbicides are classified and why it is important for managing herbicide resistance2.Understand the Importance of classification and herbicides by mode of action rather than chemical family3.Be able to tell the difference between mode of action and site of action4.Be able to differentiate between herbicide families, modes of action, and sites of action5.Understand common name, trade names and sites of absorption

320

Molecular Classifications  

Microsoft Academic Search

The field of glioma classification is currently entering a new era with the introduction of paradigms based on molecular information.\\u000a Rather than supplanting traditional morphology-based classification schemes, it is anticipated that emerging molecular biologic,\\u000a genomic, transcriptomic, and proteomic data will complement and augment existing morphologic and immunophenotypic data, providing\\u000a for a more accurate and refined stratification of glioma patients for

Gregory N. Fuller

321

Multiscale modelling and nonlinear simulation of vascular tumour growth  

PubMed Central

In this article, we present a new multiscale mathematical model for solid tumour growth which couples an improved model of tumour invasion with a model of tumour-induced angiogenesis. We perform nonlinear simulations of the multi-scale model that demonstrate the importance of the coupling between the development and remodeling of the vascular network, the blood flow through the network and the tumour progression. Consistent with clinical observations, the hydrostatic stress generated by tumour cell proliferation shuts down large portions of the vascular network dramatically affecting the flow, the subsequent network remodeling, the delivery of nutrients to the tumour and the subsequent tumour progression. In addition, extracellular matrix degradation by tumour cells is seen to have a dramatic affect on both the development of the vascular network and the growth response of the tumour. In particular, the newly developing vessels tend to encapsulate, rather than penetrate, the tumour and are thus less effective in delivering nutrients. PMID:18781303

Macklin, Paul; Anderson, Alexander R. A.; Chaplain, Mark A. J.; Cristini, Vittorio

2011-01-01

322

Systemic Effects of Non-Endocrine Tumours  

PubMed Central

Tumours of non-endocrine origin may exert deleterious effects by elaborating active principles which disturb body regulation. Systemic manifestations are fairly common with neoplasms of the lung, kidney, gastro-intestinal tract and thymus. The secretion of these tumours may have a known chemical structure (serotonin), may present hormone-like action (parathormone, antidiuretic hormone, insulinoid), or have well-defined biological properties (erythropoietin, gastrin-like principle). Tumours may stimulate endocrine glands by an unknown mechanism, producing disorders such as Cushing's syndrome, hypercalcemia, gynecomastia and hypoglycemia. Thymomas may be associated with autoimmune diseases. Tumours may extensively utilize or excrete some metabolite (glucose) or electrolyte (Na or K). Awareness of the systemic effects of various neoplasms may lead to an early diagnosis and proper treatment of these manifestations. PMID:14204555

Sullivan, James D.; Rona, George

1964-01-01

323

Mesenchymal phosphaturic tumour: early detection of recurrence.  

PubMed

The case of a recurrent phosphaturic mesenchymal tumour of the maxillary sinus 10 years after the first surgical excision is reported. The neoplasm first presented with paraneoplastic osteomalacia causing a pathological femur fracture. A right maxillary sinus tumour was identified and treated thereafter. The patient had no local symptoms and serum electrolytes returned to normal after surgical removal of the tumour. However, 10 years later, the patient's urine Ca and P levels increased and an octreoscan detected a new tumour in the right maxillary sinus. Early diagnosis prevented the effects of the paraneoplastic activity of the neoplasm. This case emphasises the importance of specific, close follow-up, because the neoplasm rarely produces local signs indicating its position. To our knowledge, this is the first reported case of a late relapse presenting without relevant symptoms (local pain or swelling or pathological fractures). PMID:24827649

Allevi, Fabiana; Rabbiosi, Dimitri; Mandalà, Marco; Colletti, Giacomo

2014-01-01

324

Case Series of Skin Adnexal Tumours  

PubMed Central

Background: Skin adnexal tumours (SATs) are a large and diverse group of benign and malignant neoplasms. They are uncommon. They can be single or multiple, sporadic or familial and they might be markers for syndromes associated with internal malignancies. Benign adnexal tumours are more common and malignant SATs are rare and are locally aggressive and have the potential for nodal involvement and distant metastasis with a poor clinical outcome.Therefore recognition of SATs and establishing a diagnosis of malignancy in SATs is important for therapeutic and prognostic reasons. Aims and Objectives: SATs are rare benign and malignant neoplasms. They are not commonly encountered in the routine surgical pathology practice.Hence this study aims at finding the frequency, clinical presentation and the histopathological appearances of SATS, and the differentiating features between benign and malignant tumours. Materials and Methods: This is partly a retrospective and partly a prospective study done in a tertiary care hospital over a period of four years .All the SATs reported during this period are analysed for their clinical features, age, sex incidence and their gross and histopathological features. Results: In the four years period 1,64,220 patients attended the hospital. The total number of SATS reported during this period were 21 cases (0.0128 %) Benign tumours were 19 (90.48%). Malignant tumours were 2(9.52%) The mean age for males 36.9 years and for females 35. Two years. There were 11 male patients and 10 female patients. Tumours of hair follicular differentiation were 7 (33.33%). Tumour like lesion of sebaceous origin was 1 (4.76%). Tumours of sweat gland origin were 11 (52.38%). Malignant tumours of eccrine origin were 2 (9.52%). Conclusion: SATs are not common. Their incidence in our study is only 0.0128 % of all cases. Eventhough benign SATs are more common than the malignant tumours, malignant SATs can occur both in young and elderly patients and they are aggressive and the SATs should be excised with wide tumour free margins. PMID:25386438

Selvakumar, Sathish; Rajeswari, K.; Meenakshisundaram, K.; G, Veena; Ramachandran, Padmini

2014-01-01

325

The hypoxic tumour microenvironment and metastatic progression  

Microsoft Academic Search

The microenvironment of solid tumours contains regions of poor oxygenation and high acidity. Growing evidence from clinical\\u000a and experimental studies points to a fundamental role for hypoxia in metastatic progression. Prolonged hypoxia increases genomic\\u000a instability, genomic heterogeneity, and may act as a selective pressure for tumour cell variants. Hypoxia can also act in\\u000a an epigenetic fashion, altering the expression of

Patrick Subarsky; Richard P. Hill

2003-01-01

326

Intraoperative radioactive localization of small bone tumours  

Microsoft Academic Search

A sodium-iodide scintillation probe and a portable scaler rate-metre were used to localize small bone tumours at operation, after the preoperative injection of technetium-99m methylene diphosphonate. This technique allows complete removal of the tumour nidus of an osteoid osteoma or the active part of other lesions without undue sacrifice of the surrounding bone. The method has been used for successful

H. De Boeck; P. P. Casteleyn; A. Bossuyt; A. Jacobs

1992-01-01

327

Exploiting tumour hypoxia in cancer treatment  

Microsoft Academic Search

Solid tumours contain regions at very low oxygen concentrations (hypoxia), often surrounding areas of necrosis. The cells in these hypoxic regions are resistant to both radiotherapy and chemotherapy. However, the existence of hypoxia and necrosis also provides an opportunity for tumour-selective therapy, including prodrugs activated by hypoxia, hypoxia-specific gene therapy, targeting the hypoxia-inducible factor 1 transcription factor, and recombinant anaerobic

William R. Wilson; J. Martin Brown

2004-01-01

328

The candidate Wilms' tumour gene is involved in genitourinary development  

Microsoft Academic Search

WILMS' tumour is an embryonic kidney tumour thought to arise through aberrant mesenchymal stem cell differentiation1 and to result from loss of function of a 'tumour suppressor' gene(s)2. Both sporadic and syndrome-associated Wilms' tumours are accompanied by an increased frequency of abnormalities of the urinary tract and genitalia3. Deletional analysis of individuals with the WAGR syndrome4-8 (for, Wilms' tumour, aniridia,

Kathryn Pritchard-Jones; Stewart Fleming; Duncan Davidson; Wendy Bickmore; David Porteous; Christine Gosden; Jonathan Bard; Alan Buckler; Jerry Pelletier; David Housman; Veronica van Heyningen; Nicholas Hastie

1990-01-01

329

Reproducibility of histologic classification of gastric cancer.  

PubMed Central

A panel review of histologic specimens was carried out as part of a multi-centre case-control study of gastric cancer (GC) and diet. Comparisons of diagnoses of 100 GCs by six pathologists revealed agreement in histologic classification for about 70-80% of the cancers. Concordance was somewhat higher when using the Lauren rather than the Ming or World Health Organization classification systems. Histologic types from reading biopsy tissue agreed with those derived from surgical specimens for 65-75% of the 100 tumours. Intra-observer agreement in histologic classification, assessed by repeat readings up to 3 years apart by one pathologist, was 95%. The findings indicate that, although overall concordance was good, it is important to standardise diagnoses in multi-centre epidemiologic studies of GC by histologic type. PMID:2039701

Palli, D.; Bianchi, S.; Cipriani, F.; Duca, P.; Amorosi, A.; Avellini, C.; Russo, A.; Saragoni, A.; Todde, P.; Valdes, E.

1991-01-01

330

ICGC PedBrain: Dissecting the genomic complexity underlying medulloblastoma  

PubMed Central

Summary Medulloblastoma is an aggressively-growing tumour, arising in the cerebellum or medulla/brain stem. It is the most common malignant brain tumour in children, and displays tremendous biological and clinical heterogeneity1. Despite recent treatment advances, approximately 40% of children experience tumour recurrence, and 30% will die from their disease. Those who survive often have a significantly reduced quality of life. Four tumour subgroups with distinct clinical, biological and genetic profiles are currently discriminated2,3. WNT tumours, displaying activated wingless pathway signalling, carry a favourable prognosis under current treatment regimens4. SHH tumours show hedgehog pathway activation, and have an intermediate prognosis2. Group 3 & 4 tumours are molecularly less well-characterised, and also present the greatest clinical challenges2,3,5. The full repertoire of genetic events driving this distinction, however, remains unclear. Here we describe an integrative deep-sequencing analysis of 125 tumour-normal pairs. Tetraploidy was identified as a frequent early event in Group 3 & 4 tumours, and a positive correlation between patient age and mutation rate was observed. Several recurrent mutations were identified, both in known medulloblastoma-related genes (CTNNB1, PTCH1, MLL2, SMARCA4) and in genes not previously linked to this tumour (DDX3X, CTDNEP1, KDM6A, TBR1), often in subgroup-specific patterns. RNA-sequencing confirmed these alterations, and revealed the expression of the first medulloblastoma fusion genes. Chromatin modifiers were frequently altered across all subgroups. These findings enhance our understanding of the genomic complexity and heterogeneity underlying medulloblastoma, and provide several potential targets for new therapeutics, especially for Group 3 & 4 patients. PMID:22832583

Jones, David TW; Jäger, Natalie; Kool, Marcel; Zichner, Thomas; Hutter, Barbara; Sultan, Marc; Cho, Yoon-Jae; Pugh, Trevor J; Hovestadt, Volker; Stütz, Adrian M; Rausch, Tobias; Warnatz, Hans-Jörg; Ryzhova, Marina; Bender, Sebastian; Sturm, Dominik; Pleier, Sabrina; Cin, Huriye; Pfaff, Elke; Sieber, Laura; Wittmann, Andrea; Remke, Marc; Witt, Hendrik; Hutter, Sonja; Tzaridis, Theophilos; Weischenfeldt, Joachim; Raeder, Benjamin; Avci, Meryem; Amstislavskiy, Vyacheslav; Zapatka, Marc; Weber, Ursula D; Wang, Qi; Lasitschka, Bärbel; Bartholomae, Cynthia C; Schmidt, Manfred; von Kalle, Christof; Ast, Volker; Lawerenz, Chris; Eils, Jürgen; Kabbe, Rolf; Benes, Vladimir; van Sluis, Peter; Koster, Jan; Volckmann, Richard; Shih, David; Betts, Matthew J; Russell, Robert B; Coco, Simona; Tonini, Gian Paolo; Schüller, Ulrich; Hans, Volkmar; Graf, Norbert; Kim, Yoo-Jin; Monoranu, Camelia; Roggendorf, Wolfgang; Unterberg, Andreas; Herold-Mende, Christel; Milde, Till; Kulozik, Andreas E; von Deimling, Andreas; Witt, Olaf; Maass, Eberhard; Rössler, Jochen; Ebinger, Martin; Schuhmann, Martin U; Frühwald, Michael C; Hasselblatt, Martin; Jabado, Nada; Rutkowski, Stefan; von Bueren, André O; Williamson, Dan; Clifford, Steven C; McCabe, Martin G; Collins, V. Peter; Wolf, Stephan; Wiemann, Stefan; Lehrach, Hans; Brors, Benedikt; Scheurlen, Wolfram; Felsberg, Jörg; Reifenberger, Guido; Northcott, Paul A; Taylor, Michael D; Meyerson, Matthew; Pomeroy, Scott L; Yaspo, Marie-Laure; Korbel, Jan O; Korshunov, Andrey; Eils, Roland; Pfister, Stefan M; Lichter, Peter

2013-01-01

331

Brain Basics: Know Your Brain  

MedlinePLUS

... dysfunctional. Image 1 < top > The Architecture of the Brain The brain is like a committee of experts. ... information that can be processed. < top > The Inner Brain Deep within the brain, hidden from view, lie ...

332

Renal and adrenal tumours in children  

PubMed Central

The differential diagnosis of renal and supra-renal masses firstly depends on the age of the child. Neuroblastoma (NBL) may be seen antenatally or in the newborn period; this tumour has a good prognosis unlike NBL seen in older children (particularly NBL in those aged 2–4 years). Benign renal masses predominate in early infancy but beyond the first year of life Wilms' tumour is the most common renal malignancy, until adolescence when renal cell carcinoma has similar or increased frequency as children get older. Adrenal adenomas and carcinomas also occur in childhood; these tumours are indistinguishable on imaging but criteria for the diagnosis of adrenal carcinoma include size larger than 5?cm, a tendency to invade the inferior vena cava and to metastasise. The most topical dilemmas in the radiological assessment of renal and adrenal tumours are presented. Topics covered include a proposed revision to the staging of NBL, the problems inherent in distinguishing nephrogenic rests from Wilms' tumour and the current recently altered approach regarding small lung nodules in children with Wilms' tumour. PMID:17339140

2007-01-01

333

Diagnosis and management of intradiverticular bladder tumours.  

PubMed

Intradiverticular bladder tumours (IDBT) account for approximately 1% of all urinary bladder tumours. The risk of developing a tumour within a bladder diverticulum is considered to be greater than in the main bladder, possibly owing to prolonged contact of potential carcinogens with the mucosal lining from urinary stasis. Patients with these tumours most commonly present with visible haematuria. Diagnostic tests include urine cytology, cystoscopy, ultrasonography, CT, MRI, and biopsy. Lack of muscle in the diverticula increases the risk of bladder perforation during biopsy and makes pathological staging difficult as there is no T2 stage; instead, data suggest that any invasion beyond the lamina propria should be described as T3. IDBT can be managed by transurethral resection and adjuvant intravesical therapy, diverticulectomy, or cystectomy (partial or radical), as outlined by the only guidelines to specifically address the management of IDBT, which were published by the Cancer Committee of the French Association of Urology (CCAFU) in 2012. The prognosis of patients with intradiverticular bladder tumours has always been perceived to be worse than those with intravesical tumours; however, the only study of 5-year survival rates for patients with IDBT suggests that prognosis might be comparable for these conditions. PMID:24934450

Walker, Nicholas Faure; Gan, Christine; Olsburgh, Jonathon; Khan, Muhammad Shamim

2014-07-01

334

A dynamical model of tumour immunotherapy.  

PubMed

A coupled ordinary differential equation model of tumour-immune dynamics is presented and analysed. The model accounts for biological and clinical factors which regulate the interaction rates of cytotoxic T lymphocytes on the surface of the tumour mass. A phase plane analysis demonstrates that competition between tumour cells and lymphocytes can result in tumour eradication, perpetual oscillations, or unbounded solutions. To investigate the dependence of the dynamic behaviour on model parameters, the equations are solved analytically and conditions for unbounded versus bounded solutions are discussed. An analytic characterisation of the basin of attraction for oscillatory orbits is given. It is also shown that the tumour shape, characterised by a surface area to volume scaling factor, influences the size of the basin, with significant consequences for therapy design. The findings reveal that the tumour volume must surpass a threshold size that depends on lymphocyte parameters for the cancer to be completely eliminated. A semi-analytic procedure to calculate oscillation periods and determine their sensitivity to model parameters is also presented. Numerical results show that the period of oscillations exhibits notable nonlinear dependence on biologically relevant conditions. PMID:24759513

Frascoli, Federico; Kim, Peter S; Hughes, Barry D; Landman, Kerry A

2014-07-01

335

An immunohistochemical study of odontogenic mixed tumours.  

PubMed

Five cases of odontogenic mixed tumour comprising of an ameloblastic fibroma, an adenomatoid odontogenic tumour, an odonto-ameloblastoma and two ameloblastic fibro-odontomas were immunohistochemically investigated. Odontogenic epithelial cells were fully positive for cytokeratin detected by antibody KL-1, although there were some differences in its intensity. In contrast, for tenascin, only immature dental papilla-like mesenchymal tissue, especially around the dental lamina-like odontogenic epithelium, was positive, while the myxomatous area and connective tissue were negative. Positive vimentin staining was observed in some areas of immature dental papilla-like cells as well as the basement membrane of odontogenic epithelium in the ameloblastic fibroma, suggesting that this tumour had developed at the early stage of tooth formation. Proliferating nuclear cell antigen-positive cells were generally rarely seen, but were frequently observed in epithelial cells of the ameloblastic fibroma and odonto-ameloblastoma. These observations suggest that tumour cells in each odontogenic mixed tumour possess characteristic proteins associated with proliferation potential and that ameloblastic fibroma and odonto-ameloblastoma have higher proliferation potential among the tumours examined. PMID:7543314

Yamamoto, K; Yoneda, K; Yamamoto, T; Ueta, E; Osaki, T

1995-03-01

336

Soft Tissue Tumours of the Retroperitoneum  

PubMed Central

Purpose. This review summarizes the more prevalent soft tissue tumours arising in the retroperitoneum and highlights some recent fundamental and diagnostic developments relevant to mesenchymal tumours. Discussion. The retroperitoneum is an underestimated site for benign and malignant neoplastic disease, and represents the second most common site of origin of primary malignant soft tissue tumours (sarcomas) after the deep tissues of the lower extremity. In contrast to the predominance of benign soft tissue lesions over malignant sarcomas elsewhere, retroperitoneal mesenchymal lesions are far more likely to be malignant. The differential diagnosis is primarily with the more common lymphoproliferative and parenchymatous epithelial lesions arising in this area, and with metastatic disease from known or unknown primary sites elsewhere.The most prevalent mesenchymal tumours at this site are of a lipomatous, myogenic or neural nature.Their generally late clinical presentation and poorly accessible location provides numerous clinical challenges; optimal radiological imaging and a properly performed biopsy are essential cogs in the management route. Histopathological diagnosis may be complicated, but has been aided by developments in the fields of immunohistochemistry and tumour (cyto)genetics. Despite significant advances in oncological management protocols, the prognosis remains generally less favourable than for similar tumours at more accessible sites. PMID:18521430

Van Roggen, J. Frans Graadt

2000-01-01

337

Functional Brain Imaging  

PubMed Central

Executive Summary Objective The objective of this analysis is to review a spectrum of functional brain imaging technologies to identify whether there are any imaging modalities that are more effective than others for various brain pathology conditions. This evidence-based analysis reviews magnetoencephalography (MEG), magnetic resonance spectroscopy (MRS), positron emission tomography (PET), and functional magnetic resonance imaging (fMRI) for the diagnosis or surgical management of the following conditions: Alzheimer’s disease (AD), brain tumours, epilepsy, multiple sclerosis (MS), and Parkinson’s disease (PD). Clinical Need: Target Population and Condition Alzheimer’s disease is a progressive, degenerative, neurologic condition characterized by cognitive impairment and memory loss. The Canadian Study on Health and Aging estimated that there will be 97,000 incident cases (about 60,000 women) of dementia (including AD) in Canada in 2006. In Ontario, there will be an estimated 950 new cases and 580 deaths due to brain cancer in 2006. Treatments for brain tumours include surgery and radiation therapy. However, one of the limitations of radiation therapy is that it damages tissue though necrosis and scarring. Computed tomography (CT) and magnetic resonance imaging (MRI) may not distinguish between radiation effects and resistant tissue, creating a potential role for functional brain imaging. Epilepsy is a chronic disorder that provokes repetitive seizures. In Ontario, the rate of epilepsy is estimated to be 5 cases per 1,000 people. Most people with epilepsy are effectively managed with drug therapy; but about 50% do not respond to drug therapy. Surgical resection of the seizure foci may be considered in these patients, and functional brain imaging may play a role in localizing the seizure foci. Multiple sclerosis is a progressive, inflammatory, demyelinating disease of the central nervous system (CNS). The cause of MS is unknown; however, it is thought to be due to a combination of etiologies, including genetic and environmental components. The prevalence of MS in Canada is 240 cases per 100,000 people. Parkinson’s disease is the most prevalent movement disorder; it affects an estimated 100,000 Canadians. Currently, the standard for measuring disease progression is through the use of scales, which are subjective measures of disease progression. Functional brain imaging may provide an objective measure of disease progression, differentiation between parkinsonian syndromes, and response to therapy. The Technology Being Reviewed Functional Brain Imaging Functional brain imaging technologies measure blood flow and metabolism. The results of these tests are often used in conjunction with structural imaging (e.g., MRI or CT). Positron emission tomography and MRS identify abnormalities in brain tissues. The former measures abnormalities through uptake of radiotracers in the brain, while the latter measures chemical shifts in metabolite ratios to identify abnormalities. The potential role of functional MRI (fMRI) is to identify the areas of the brain responsible for language, sensory and motor function (sensorimotor cortex), rather than identifying abnormalities in tissues. Magnetoencephalography measures magnetic fields of the electric currents in the brain, identifying aberrant activity. Magnetoencephalography may have the potential to localize seizure foci and to identify the sensorimotor cortex, visual cortex and auditory cortex. In terms of regulatory status, MEG and PET are licensed by Health Canada. Both MRS and fMRI use a MRI platform; thus, they do not have a separate licence from Health Canada. The radiotracers used in PET scanning are not licensed by Health Canada for general use but can be used through a Clinical Trials Application. Review Strategy The literature published up to September 2006 was searched in the following databases: MEDLINE, MEDLINE In-Process & Other Non-Indexed Citations, EMBASE, Cochrane Database of Systematic Reviews, CENTRAL, and International Network of Agencies for H

2006-01-01

338

Genetic changes in tumour microenvironments.  

PubMed

Numerous in vitro and in vivo studies have established that carcinoma-associated fibroblasts differ phenotypically from fibroblasts associated with normal tissue but the mechanisms underlying these differences are unclear. Since carcinoma-associated fibroblasts can be propagated in vitro for extended periods and still maintain their cancer-promoting phenotype, some investigators have proposed that they might have acquired somatic genetic alterations analogous to those observed in malignant epithelium. Early molecular genetic studies appeared to validate this hypothesis by demonstrating remarkably high frequencies of clonal somatic genetic alterations in carcinoma-associated fibroblasts, including loss of heterozygosity, gene amplification, and point mutations in tumour suppressor genes such as TP53 and PTEN. The initial excitement of these paradigm-changing studies overshadowed concerns that there may have been a more mundane explanation for these observations. In addition to the fact that the data would necessarily invoke an unlikely scenario of the simultaneous generation of two symbiotic malignancies, subsequent molecular genetic studies found no evidence of frequent genomic aberrations. One striking common trait of those studies reporting frequent clonal somatic alterations in carcinoma-associated fibroblasts is the use of tissues and techniques which are well known to be highly prone to generating artefacts such as limiting and poor quality DNA followed by highly multiplexed PCR-based analyses. It is now clear that clonal somatic mutations are not the biological basis of the cancer-promoting attributes of carcinoma-associated fibroblasts. PMID:21294119

Campbell, Ian; Qiu, Wen; Haviv, Izhak

2011-03-01

339

Chemoresistance in rat ovarian tumours.  

PubMed

In a cisplatin resistant subline (O-342/DPP) of an intraperitoneally growing transplantable rat ovarian tumour (O-342), intracellular glutathione (GSH) was approximately doubled (mean [S.E.] 1.5 [0.26] vs. 0.8 [0.2] nmol/10(6) cells). GSH reductase activity was higher (30.64 [4.07] vs. 20 [0.92] nmol/min per mg protein), although no difference was found for GSH-S-transferase. 24 h after exposure to cisplatin, formation of DNA interstrand cross-links was at a maximum in both lines and significantly higher in O-342 (162 [23] vs. 88 [22] rad eq). Combination treatment of O-342/DDP with buthionine sulphoximine plus cisplatin resulted in a marginal increase in survival compared with cisplatin treatment; treatment of this line with 3-aminobenzamide plus cisplatin was also superior to cisplatin alone. In the sensitive line both combinations were likewise superior to cisplatin alone. In vitro, at equimolar concentration, a new platinum complex (CTDP) was at least as active as cisplatin in both lines, which suggests a superior therapeutic index because its LD50 in mice is threefold higher than that of cisplatin. A ruthenium complex (ICR) had a higher activity in the resistant line. A titanium complex (budotitane) was not active. PMID:1826445

Zeller, W J; Frühauf, S; Chen, G; Keppler, B K; Frei, E; Kaufmann, M

1991-01-01

340

Keratocystic odontogenic tumour: systematic review  

PubMed Central

Objectives The aim of this review is to evaluate the principal clinical and conventional radiographic features of non-syndromic keratocystic odontogenic tumour (KCOT) by systematic review (SR), and to compare the frequencies between four global groups. Methods The databases searched were the PubMed interface of Medline and LILACS. Only those reports of KCOTs that occurred in a series of consecutive cases, in the reporting authors' caseload, were considered. Results 51 reports, of 49 series of cases, were included in the SR. 11 SR-included series were in languages other than English. KCOTs affected males more frequently and were three times more prevalent in the mandible. Although the mean age at first presentation was 37 years, the largest proportion of cases first presented in the third decade. The main symptom was swelling. Over a third were found incidentally. Nearly two-thirds displayed buccolingual expansion. Over a quarter of cases recurred. Only a quarter of all SR-included reported series of cases included details of at least one radiological feature. The East Asian global group presented significantly as well-defined, even corticated, multilocular radiolucencies with buccolingual expansion. The KCOTs affecting the Western global group significantly displayed an association with unerupted teeth. Conclusions Long-term follow-up of large series that would have revealed detailed radiographic description and long-term outcomes of non-syndromic KCOT was lacking. PMID:21159911

MacDonald-Jankowski, D S

2011-01-01

341

The association between renal tumour scoring system components and complications of partial nephrectomy  

PubMed Central

Introduction: We evaluate the associations between 3 renal tumour scoring systems and their components with perioperative complications of partial nephrectomy. Methods: A consecutive cohort of partial nephrectomy patients was analyzed. Patient characteristics were abstracted from medical records. PADUA scores (preoperative aspects and dimensions used for anatomic classification), RENAL (radius exophyic/endophytic nearness anterior/posterior location scoring) nephrometry scores, and Centrality index (C-index) were determined from preoperative axial images by 2 independent reviewers. Cases were evaluated for postoperative complications up to 30 days after surgery. Pre-specified complication definitions were used for 33 potential medical and surgical complications. Unadjusted and adjusted associations between overall scores, individual components, and complications were determined using log binomial regression. Results: In total, 118 patients were included in the study. Of these, 36 (30.5%) surgical complications occurred in 27 (22.9%) patients. Fourteen (11.9%) were Clavien grade ?3. Overall PADUA score was significantly associated with surgical and overall complications after adjusting for potential confounders. Among all components of the 3 scoring systems, only tumour diameter and exophytic/endophytic nature of the tumour were significantly associated with complications after adjusting for the other components of the respective scoring system (p < 0.05). Conclusions: Renal tumour scoring systems may help predict the risk of complications after partial nephrectomy. Further refinement of current systems is required. A first step would be to include only components that are significantly associated with complications. PMID:25737754

Desantis, Darren; Lavallée, Luke T.; Witiuk, Kelsey; Mallick, Ranjeeta; Kamal, Fadi; Fergusson, Dean; Morash, Christopher; Cagiannos, Ilias; Breau, Rodney H.

2015-01-01

342

Brain-only metastases of small cell lung cancer; efficacy of whole brain radiotherapy. An EORTC phase II study  

Microsoft Academic Search

Background and purpose: To evaluate the efficacy of WBRT as a single treatment modality in patients with brain metastases of small cell lung cancer.Patients and methods: The patients had brain metastases of small cell lung cancer without any sign of tumour outside the brain and were treated with 10×3.0 Gy WBRT. Response and neurological functions were evaluated after 6, 18

Pieter E Postmus; Hanny Haaxma-Reiche; Anna Gregor; Harry J. M Groen; Tadeus Lewinski; Tindaro Scolard; Anne Kirkpatrick; Desmond Curran; Tarek Sahmoud; Guiseppe Giaccone

1998-01-01

343

Tumour nuclear oestrogen receptor beta 1 correlates inversely with parathyroid tumour weight  

PubMed Central

Primary hyperparathyroidism (PHPT) is a common endocrinopathy, frequently caused by a parathyroid adenoma, rarely by a parathyroid carcinoma that lacks effective oncological treatment. As the majority of cases are present in postmenopausal women, oestrogen signalling has been implicated in the tumourigenesis. Oestrogen receptor beta 1 (ERB1) and ERB2 have been recently identified in parathyroid adenomas, the former inducing genes coupled to tumour apoptosis. We applied immunohistochemistry and slide digitalisation to quantify nuclear ERB1 and ERB2 in 172 parathyroid adenomas, atypical adenomas and carcinomas, and ten normal parathyroid glands. All the normal parathyroid glands expressed ERB1 and ERB2. The majority of tumours expressed ERB1 (70.6%) at varying intensities, and ERB2 (96.5%) at strong intensities. Parathyroid carcinomas expressed ERB1 in three out of six cases and ERB2 in five out of six cases. The intensity of tumour nuclear ERB1 staining significantly correlated inversely with tumour weight (P=0.011), and patients whose tumours were classified as ERB1-negative had significantly greater tumour weight as well as higher serum calcium (P=0.002) and parathyroid hormone levels (P=0.003). Additionally, tumour nuclear ERB1 was not expressed differentially with respect to sex or age of the patient. Levels of tumour nuclear ERB2 did not correlate with clinical characteristics. In conclusion, decreased ERB1 immunoreactivity is associated with increased tumour weight in parathyroid adenomas. Given the previously reported correlation with tumour-suppressive signalling, selective oestrogen receptor modulation (SERMs) may play a role in the treatment of parathyroid carcinomas. Future studies of SERMs and oestrogen treatment in PHPT should consider tumour weight as a potential factor in pharmacological responsiveness. PMID:25648860

Haglund, Felix; Rosin, Gustaf; Nilsson, Inga-Lena; Juhlin, C Christofer; Pernow, Ylva; Norenstedt, Sophie; Dinets, Andrii; Larsson, Catharina; Hartman, Johan; Höög, Anders

2015-01-01

344

Classification Fun  

NSDL National Science Digital Library

Taxonomic information shows the evolutionary relationships between organisms. In this lesson plan, students will classify organisms by kingdom and apply their own understanding of classification to identify organisms. The students should already have an understanding of the basics of the five kindoms and the seven categories of classification. The document includes a pre-test on the topic to gauge student understanding and two classroom activities. The activity is intended for sixth grade students, and should take three to four class periods to complete.

Shubinski, Carol

2012-06-11

345

Inhibition of apoptosis in human tumour cells by the tumour-associated serpin, SCC antigen-1  

PubMed Central

The squamous cell carcinoma antigen (SCC Ag) is a tumour-associated protein and a member of theserineproteaseinhibitor (serpin) family. The SCC Ag has been used as a serologic tumour marker for SCC progression, and its elevated serum levels are a risk factor for disease relapse. However, the biologic significance of this intracytoplasmic protein in cancer cells remains unknown. In this report, we demonstrated that apoptosis induced by 7-ethyl-10-hydroxycamptothecin, tumour necrosis factor-? (TNF-?) or interleukin (IL)-2-activated natural killer (NK) cells was significantly inhibited in tumour cells transduced with the SCC Ag-1 cDNA, as compared to control cells in vitro. Also, inhibition of the SCC Ag-1 expression in tumour cells by transfection of antisense SCC Ag-1 cDNA was accompanied by significantly increased sensitivity of these cells to apoptosis induced by etoposide or TNF-?. The mechanism of protection of tumour cells from apoptosis involved inhibition of caspase-3 activity and/or upstream proteases. In vivo, tumour cells overexpressing the SCC Ag-1 formed significantly larger tumours in nude mice than the SCC Ag-1-negative controls. Thus, overexpression of the SCC Ag-1, a member of the serpin family, in human cancer cells contributed to their survival by mediating protection from drug-, cytokine- or effector cell-induced apoptosis. © 2000 Cancer Research Campaign PMID:10732775

Suminami, Y; Nagashima, S; Vujanovic, N L; Hirabayashi, K; Kato, H; Whiteside, T L

2000-01-01

346

Tumour-to-tumour metastasis: male breast carcinoma metastasis arising in an extrapleural solitary fibrous tumour ¿ a case report.  

PubMed

BackgroundTumour-to-tumour metastasis (TTM) occurs when one tumour metastasises to a separate tumour within the same individual. TTM is observed frequently in breast cancer but has not been described in male breast cancer. In addition reports describing solitary fibrous tumours (SFT) of the pleura hosting other neoplasms¿ metastases are limited. We report an exceptional case of male breast cancer metastasising to an extrapleural SFT, occurring in the subcutaneous tissue of the back of a 68-year old Caucasian patient.Case presentationA 68-year old male was diagnosed with a metastasising ductal breast cancer. He was treated by mastectomy of the right breast and axillary lymph-adenectomy. Further staging revealed an increasing subcutaneous expansion located on the patient¿s back. Excision biopsy confirmed a SFT hosting a breast cancer metastasis. The patient received palliative chemotherapy but died of disease seven years after initial diagnosis.ConclusionsThe abundance of blood vessels within these lesions might predispose SFTs for an involvement in TTM. This case describes the possibility of concurrent rare occurrences and reminds clinicians, as well as pathologists, to be open-minded and fastidious about their differential diagnoses, sampling and examination of histological specimens.Virtual SlidesThe virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/13000_2014_203. PMID:25420931

Scheipl, Susanne; Moinfar, Farid; Leithner, Andreas; Sadoghi, Patrick; Jorgensen, Mette; Rinner, Beate; Liegl, Bernadette

2014-11-25

347

Tumour resistance to cisplatin: a modelling approach  

NASA Astrophysics Data System (ADS)

Although chemotherapy has revolutionized the treatment of haematological tumours, in many common solid tumours the success has been limited. Some of the reasons for the limitations are: the timing of drug delivery, resistance to the drug, repopulation between cycles of chemotherapy and the lack of complete understanding of the pharmacokinetics and pharmacodynamics of a specific agent. Cisplatin is among the most effective cytotoxic agents used in head and neck cancer treatments. When modelling cisplatin as a single agent, the properties of cisplatin only have to be taken into account, reducing the number of assumptions that are considered in the generalized chemotherapy models. The aim of the present paper is to model the biological effect of cisplatin and to simulate the consequence of cisplatin resistance on tumour control. The 'treated' tumour is a squamous cell carcinoma of the head and neck, previously grown by computer-based Monte Carlo techniques. The model maintained the biological constitution of a tumour through the generation of stem cells, proliferating cells and non-proliferating cells. Cell kinetic parameters (mean cell cycle time, cell loss factor, thymidine labelling index) were also consistent with the literature. A sensitivity study on the contribution of various mechanisms leading to drug resistance is undertaken. To quantify the extent of drug resistance, the cisplatin resistance factor (CRF) is defined as the ratio between the number of surviving cells of the resistant population and the number of surviving cells of the sensitive population, determined after the same treatment time. It is shown that there is a supra-linear dependence of CRF on the percentage of cisplatin-DNA adducts formed, and a sigmoid-like dependence between CRF and the percentage of cells killed in resistant tumours. Drug resistance is shown to be a cumulative process which eventually can overcome tumour regression leading to treatment failure.

Marcu, L.; Bezak, E.; Olver, I.; van Doorn, T.

2005-01-01

348

Is it Possible to Extract Brain Metabolic Pathways Information from In Vivo H Nuclear Magnetic Resonance Spectroscopy Data?  

E-print Network

In vivo H nuclear magnetic resonance (NMR) spectroscopy is an important tool for performing non-invasive quantitative assessments of brain tumour glucose metabolism. Brain tumours are considered as fast-growth tumours because of their high rate of proliferation. In addition, tumour cells exhibit profound genetic, biochemical and histological differences with respect to the original non-transformed cellular types. Therefore, there is a strong interest from the clinical investigator point of view in understanding the role of brain metabolites in normal and pathological conditions and especially on the development of early tumour detection techniques. Unfortunately, current diagnosis techniques ignore the dynamic aspects of these signals. It is largely believed that temporal variations of NMR Spectra are noisy or just simply do not carry enough information to be exploited by any reliable diagnosis procedure. Thus, current diagnosis procedures are mainly based on empirical observations extracted from single avera...

de Lara, Alejandro Chinea Manrique

2010-01-01

349

Naturally occurring tumours in the basal metazoan Hydra.  

PubMed

The molecular nature of tumours is well studied in vertebrates, although their evolutionary origin remains unknown. In particular, there is no evidence for naturally occurring tumours in pre-bilaterian animals, such as sponges and cnidarians. This is somewhat surprising given that recent computational studies have predicted that most metazoans might be prone to develop tumours. Here we provide first evidence for naturally occurring tumours in two species of Hydra. Histological, cellular and molecular data reveal that these tumours are transplantable and might originate by differentiation arrest of female gametes. Growth of tumour cells is independent from the cellular environment. Tumour-bearing polyps have significantly reduced fitness. In addition, Hydra tumours show a greatly altered transcriptome that mimics expression shifts in vertebrate cancers. Therefore, this study shows that spontaneous tumours have deep evolutionary roots and that early branching animals may be informative in revealing the fundamental mechanisms of tumorigenesis. PMID:24957317

Domazet-Lošo, Tomislav; Klimovich, Alexander; Anokhin, Boris; Anton-Erxleben, Friederike; Hamm, Mailin J; Lange, Christina; Bosch, Thomas C G

2014-01-01

350

Critical transitions in a game theoretic model of tumour metabolism  

PubMed Central

Tumour proliferation is promoted by an intratumoral metabolic symbiosis in which lactate from stromal cells fuels energy generation in the oxygenated domain of the tumour. Furthermore, empirical data show that tumour cells adopt an intermediate metabolic state between lactate respiration and glycolysis. This study models the metabolic symbiosis in the tumour through the formalism of evolutionary game theory. Our game model of metabolic symbiosis in cancer considers two types of tumour cells, hypoxic and oxygenated, while glucose and lactate are considered as the two main sources of energy within the tumour. The model confirms the presence of multiple intermediate stable states and hybrid energy strategies in the tumour. It predicts that nonlinear interaction between two subpopulations leads to tumour metabolic critical transitions and that tumours can obtain different intermediate states between glycolysis and respiration which can be regulated by the genomic mutation rate. The model can apply in the epithelial–stromal metabolic decoupling therapy. PMID:25097747

Kianercy, Ardeshir; Veltri, Robert; Pienta, Kenneth J.

2014-01-01

351

Clinical relevance associated to the analysis of circulating tumour cells in patients with solid tumours.  

PubMed

The distant growth of tumour cells escaping from primary tumours, a process termed metastasis, represents the leading cause of death among patients affected by malignant neoplasias from breast and colon. During the metastasis process, cancer cells liberated from primary tumour tissue, also termed circulating tumour cells (CTCs), travel through the circulatory and/or lymphatic systems to reach distant organs. The early detection and the genotypic and phenotypic characterisation of such CTCs could represent a powerful diagnostic tool of the disease, and could also be considered an important predictive and prognostic marker of disease progression and treatment response. In this article we discuss the potential relevance in the clinic of monitoring CTCs from patients suffering from solid epithelial tumours, with emphasis on the impact of such analyses as a predictive marker for treatment response. PMID:19828408

Serrano Fernádez, María José; Alvarez Merino, Juan Carlos; Martínez Zubiaurre, Iñigo; Fernández García, Ana; Sánchez Rovira, Pedro; Lorente Acosta, José Antonio

2009-10-01

352

Vascular tumours in infants. Part I: benign vascular tumours other than infantile haemangioma.  

PubMed

Vascular anomalies can be subdivided into vascular tumours and vascular malformations (VMs). While most VMs are present at birth and do not exhibit significant postnatal growth, vascular tumours are characterized by their dynamics of growth and (sometimes) spontaneous regression. This review focuses on benign vascular tumours other than infantile haemangiomas (IHs), namely pyogenic granuloma, eruptive pseudoangiomatosis, glomangioma, rapidly involuting and noninvoluting congenital haemangioma, verrucous haemangioma and spindle cell haemangioma. While some of them bear clinical resemblance to IH, they can be separated by age of appearance, growth characteristics and/or negative staining for glucose transporter 1. Separation of these tumours from IH is necessary because their outcome and therapeutic options are different. Semimalignant and malignant vascular tumours will be addressed in a separate review. PMID:24117053

Hoeger, P H; Colmenero, I

2014-09-01

353

Image Classification  

NSDL National Science Digital Library

In this exercise, students get experience with image classification. Images are an increasingly important source of information about land cover and land use over time because comparisons of historic and current images can provide an estimate of change in the landscape.

Cote, Paul

354

Prospective therapies for high-grade glial tumours: A literature review.  

PubMed

After three decades of intensive research, cytoreductive surgery remains the gold standard of treatment of malignant gliomas. Survivorship at both 1-year and 5-years has not drastically changed in the UK. Concomitant chemo- and radiotherapy has enhanced the efficiency of surgery, enabling more aggressive tumour resection whilst also preserving the surrounding healthy brain parenchyma. More accurate imaging techniques have also played a role in tumour identification, key to this has been pre- and intra-operative contrast enhancement and compounds that have a high affinity in binding to glioma cells. Intra-operative imaging has heralded the ability to give the operating surgeon continuous feedback to assess the completeness of resection. Research is shifting into investigating the complex cellular and molecular glial tumour-genesis, and has led to the development of efficacious chemotherapy agents and trial novel therapies. Oncolytic virotherapy has shown promise in clinical trials and gene therapy in-vitro studies. Surgery however remains the primary therapeutic option for the management of malignant gliomas removing the mass of proliferating malignant tumour cells and decompression of the space-occupying lesion. PMID:25568787

Talibi, Sayed Samed; Talibi, Sayed Samie; Aweid, Bashaar; Aweid, Osama

2014-09-01

355

Widely Infiltrating Epithelioid Malignant Peripheral Nerve Sheath Tumour of Skull Base  

PubMed Central

The epithelioid variant of malignant peripheral nerve sheath tumours is a rare histological entity, and the occurrence of a malignant peripheral nerve sheath tumour in the skull base is even more unusual. We report a case of a 52-year-old man who presented with reduced hearing in the left ear, giddiness and left-sided facial weakness of short duration. He was a known hypertensive. On examination, left-sided 7th to 12th cranial nerve palsies were noted. Computed tomography (CT) and brain magnetic resonance imaging (MRI) were reported as an ill-defined heterogeneously enhancing mass left skull base suggestive of chondrosarcoma. Left tympanotomy and biopsy of the lesion were carried out. On light microscopy and immunohistochemical examination of the biopsy, a diagnosis of epithelioid malignant peripheral nerve sheath tumour was established. The patient underwent left extended modified radical mastoidectomy and selective neck dissection. Histopathological study of the resected surgical specimen confirmed left-sided extensive tumour involvement of skull base structures, as well as neck nodal metastases. PMID:23983583

Parampalli Srinivas, Srilatha; Rao, Lakshmi; Nayak, Deepak Ranjan

2013-01-01

356

Prospective therapies for high-grade glial tumours: A literature review  

PubMed Central

After three decades of intensive research, cytoreductive surgery remains the gold standard of treatment of malignant gliomas. Survivorship at both 1-year and 5-years has not drastically changed in the UK. Concomitant chemo- and radiotherapy has enhanced the efficiency of surgery, enabling more aggressive tumour resection whilst also preserving the surrounding healthy brain parenchyma. More accurate imaging techniques have also played a role in tumour identification, key to this has been pre- and intra-operative contrast enhancement and compounds that have a high affinity in binding to glioma cells. Intra-operative imaging has heralded the ability to give the operating surgeon continuous feedback to assess the completeness of resection. Research is shifting into investigating the complex cellular and molecular glial tumour-genesis, and has led to the development of efficacious chemotherapy agents and trial novel therapies. Oncolytic virotherapy has shown promise in clinical trials and gene therapy in-vitro studies. Surgery however remains the primary therapeutic option for the management of malignant gliomas removing the mass of proliferating malignant tumour cells and decompression of the space-occupying lesion. PMID:25568787

Talibi, Sayed Samed; Talibi, Sayed Samie; Aweid, Bashaar; Aweid, Osama

2014-01-01

357

Widely infiltrating epithelioid malignant peripheral nerve sheath tumour of skull base.  

PubMed

The epithelioid variant of malignant peripheral nerve sheath tumours is a rare histological entity, and the occurrence of a malignant peripheral nerve sheath tumour in the skull base is even more unusual. We report a case of a 52-year-old man who presented with reduced hearing in the left ear, giddiness and left-sided facial weakness of short duration. He was a known hypertensive. On examination, left-sided 7th to 12th cranial nerve palsies were noted. Computed tomography (CT) and brain magnetic resonance imaging (MRI) were reported as an ill-defined heterogeneously enhancing mass left skull base suggestive of chondrosarcoma. Left tympanotomy and biopsy of the lesion were carried out. On light microscopy and immunohistochemical examination of the biopsy, a diagnosis of epithelioid malignant peripheral nerve sheath tumour was established. The patient underwent left extended modified radical mastoidectomy and selective neck dissection. Histopathological study of the resected surgical specimen confirmed left-sided extensive tumour involvement of skull base structures, as well as neck nodal metastases. PMID:23983583

Parampalli Srinivas, Srilatha; Rao, Lakshmi; Nayak, Deepak Ranjan

2013-03-01

358

Phylogenetic Quantification of Intra-tumour Heterogeneity  

PubMed Central

Intra-tumour genetic heterogeneity is the result of ongoing evolutionary change within each cancer. The expansion of genetically distinct sub-clonal populations may explain the emergence of drug resistance, and if so, would have prognostic and predictive utility. However, methods for objectively quantifying tumour heterogeneity have been missing and are particularly difficult to establish in cancers where predominant copy number variation prevents accurate phylogenetic reconstruction owing to horizontal dependencies caused by long and cascading genomic rearrangements. To address these challenges, we present MEDICC, a method for phylogenetic reconstruction and heterogeneity quantification based on a Minimum Event Distance for Intra-tumour Copy-number Comparisons. Using a transducer-based pairwise comparison function, we determine optimal phasing of major and minor alleles, as well as evolutionary distances between samples, and are able to reconstruct ancestral genomes. Rigorous simulations and an extensive clinical study show the power of our method, which outperforms state-of-the-art competitors in reconstruction accuracy, and additionally allows unbiased numerical quantification of tumour heterogeneity. Accurate quantification and evolutionary inference are essential to understand the functional consequences of tumour heterogeneity. The MEDICC algorithms are independent of the experimental techniques used and are applicable to both next-generation sequencing and array CGH data. PMID:24743184

Schwarz, Roland F.; Trinh, Anne; Sipos, Botond; Brenton, James D.; Goldman, Nick; Markowetz, Florian

2014-01-01

359

Improving tumour heterogeneity MRI assessment with histograms  

PubMed Central

By definition, tumours are heterogeneous. They are defined by marked differences in cells, microenvironmental factors (oxygenation levels, pH, VEGF, VPF and TGF-?) metabolism, vasculature, structure and function that in turn translate into heterogeneous drug delivery and therapeutic outcome. Ways to estimate quantitatively tumour heterogeneity can improve drug discovery, treatment planning and therapeutic responses. It is therefore of paramount importance to have reliable and reproducible biomarkers of cancerous lesions' heterogeneity. During the past decade, the number of studies using histogram approaches increased drastically with various magnetic resonance imaging (MRI) techniques (DCE-MRI, DWI, SWI etc.) although information on tumour heterogeneity remains poorly exploited. This fact can be attributed to a poor knowledge of the available metrics and of their specific meaning as well as to the lack of literature references to standardised histogram methods with which surrogate markers of heterogeneity can be compared. This review highlights the current knowledge and critical advances needed to investigate and quantify tumour heterogeneity. The key role of imaging techniques and in particular the key role of MRI for an accurate investigation of tumour heterogeneity is reviewed with a particular emphasis on histogram approaches and derived methods. PMID:25268373

Just, N

2014-01-01

360

The diagnosis of soft tissue tumours.  

PubMed Central

We prospectively analysed methods of diagnosis in 118 patients referred for definitive treatment with documented or presumed soft tissue sarcoma (STS). Of 65 patients with primary STS, 54 were biopsied before referral. Of these, 5 (9%) were biopsied by Tru-cut biopsy, 17 (32%) by incisional biopsy and 32 (59%) by excisional biopsy. The remaining 11 patients with primary STS, referred without biopsy, were all diagnosed by Tru-cut biopsy. An additional eight patients suspected of having STS were referred without biopsy and were found to have malignant tumours other than STS involving soft tissue by Tru-cut biopsy. Nineteen patients were proved to have benign soft tissue tumours; in 13 presumed to have STS, the diagnosis was unknown at referral. In four of these, biopsy was inappropriate. Of nine submitted to Tru-cut biopsy, an unequivocal diagnosis was made in 5 (56%) and incisional biopsy was required in the other four. Therefore, paradoxically, benign soft tissue tumours may be more difficult to diagnose with Tru-cut biopsy than malignant tumours. This study confirms the high degree of accuracy of Tru-cut biopsy in diagnosing malignant soft tissue tumours and highlights the disadvantages of open biopsy techniques. PMID:1416683

Serpell, J. W.; Fish, S. H.; Fisher, C.; Thomas, J. M.

1992-01-01

361

Chest wall tumour following iodized talc pleurodesis  

PubMed Central

Jackson, J. W., and Bennett, M. H. (1973).Thorax, 28, 788-793. Chest wall tumour following iodized talc pleurodesis. A man of 37 had an iodized talc pleurodesis carried out for recurrent spontaneous pneumothorax. There was no history of industrial exposure to asbestos. Two years later he presented with pain in the right chest and radiographs at that time showed some localized pleural thickening at the site of the thoracoscopy cannulation for introduction of talc. A provisional diagnosis of talc granuloma, chemical abscess or tumour was made and exploratory thoracotomy revealed a tumour involving the chest wall, lung, and pleura which, on histological examination, showed adenocarcinoma of varying degrees of differentiation and in some parts also presenting a more squamoid appearance. Numerous doubly refractile talc particles were intimately associated with the tumour and fibrous tissue. Shortly after excision the patient developed evidence of systemic dissemination of the disease and died four months later. The possibility of this tumour being induced by the talc is discussed. A brief review is made of the various forms of talc used in surgery over the past 40 years and attention is drawn to the significance of the proportion of asbestos mineral which is present in talc as mined in various parts of the world. We do not consider that this is a case of mesothelioma of the pleura. Images PMID:4787992

Jackson, John W.; Bennett, M. H.

1973-01-01

362

Canine transmissible venereal tumour: a morphological and immunohistochemical study of 11 tumours in growth phase and during regression after chemotherapy.  

PubMed

Eleven dogs with canine transmissible venereal tumour (CTVT) were given vincristine sulphate chemotherapy to induce tumour regression. Biopsy specimens were collected from tumours during the growth phase, before chemotherapy, and again from the same dogs during the regression induced by chemotherapy. Laboratory assessment included cytology, histology, the number of tumour cells in relation to the number of intratumoral leucocytes, proliferative and apoptotic fractions of tumour cells, intratumoral vessel density, and fibrosis. The results revealed that during regression, tumour cell proliferation ceased, apoptosis increased, leucocytes increased (with increased proportion of T lymphocytes), tumour parenchyma collapsed around intratumoral vessels, and fibrosis increased. These results, which were similar to findings in dogs with spontaneous regression of CTVT, suggest that tumour immunity plays a role in tumour regression after modest chemotherapy. PMID:10805977

Gonzalez, C M; Griffey, S M; Naydan, D K; Flores, E; Cepeda, R; Cattaneo, G; Madewell, B R

2000-05-01

363

Effect of ploidy, recruitment, environmental factors, and tamoxifen treatment on the expression of sigma-2 receptors in proliferating and quiescent tumour cells  

PubMed Central

Recently, we demonstrated that sigma-2 receptors may have the potential to be a biomarker of tumour cell proliferation (Mach et al (1997) Cancer Res57: 156–161). If sigma-2 receptors were a biomarker of tumour cell proliferation, they would be amenable to detection by non-invasive imaging procedures, thus eliminating many of the problems associated with the flow cytometric measures of tumour cell proliferation presently used in the clinic. To be a good biomarker of tumour cell proliferation, the expression of sigma-2 receptors must be essentially independent of many of the biological, physiological, and/or environmental properties that are found in solid tumours. In the investigation reported here, the mouse mammary adenocarcinoma lines, 66 (diploid) and 67 (aneuploid), 9L rat brain tumour cells, and MCF-7 human breast tumour cells were used to study the extent and kinetics of expression of sigma-2 receptors in proliferative (P) and quiescent (Q) tumour cells as a function of species, cell type, ploidy, pH, nutrient depletion, metabolic state, recruitment from the Q-cell compartment to the P-cell compartment, and treatment with tamoxifen. In these experiments, the expression of sigma-2 receptors solely reflected the proliferative status of the tumour cells. None of the biological, physiological, or environmental properties that were investigated had a measurable effect on the expression of sigma-2 receptors in these model systems. Consequently, these data suggest that the proliferative status of tumours and normal tissues can be non-invasively assessed using radiolabelled ligands that selectively bind sigma-2 receptors. © 1999 Cancer Research Campaign PMID:10576647

Al-Nabulsi, I; Mach, R H; Wang, L-M; Wallen, C A; Keng, P C; Sten, K; Childers, S R; Wheeler, K T

1999-01-01

364

Epidemiology, diagnostics and treatment of vascular tumours and malformations.  

PubMed

Vascular tumours and vascular malformations are common vasculose anomalies characteristic for dissimilar clinical course, specific biological as well as immune cytological and histological properties. Vascular lesions classification system and their detailed division into groups and subgroups were elaborated and implemented in Rome, in 1996, during meeting of the International Society for the Study of Vascular Anomalies (ISSVA). It was based on modification of an earlier going division by Mullikien and G?owacki from 1982. Infantile hemangiomas are the most numerous group of benign tumours of mesenchymal origin. Vascular malformations appear definitely less often. They are composed of normal endothelium lined displastic vessels which originate from vascular tissue abnormal morphogenesis. In contrast, in hemangiomas, at the proliferation stage, increased, multiplication of endothelial cells is observed as well as of fibroblasts, mastocytes and macrophages. Infantile hemangiomas are usually not present at the moment of birth and white chloasma with superficial teleangiectasis appears which increases within 3-4 weeks and gets bright red colour and reveal very characteristic clinical course basing on intensive growth period and involution long process. Vascular malformations are observed most often at the delivery moment or they may appear at an early childhood. They enlarge proportionally along with the child's growth and their sudden expansion may be triggered by an infection, hormonal changes or trauma. Contrary to hemangiomas, they do not subside spontaneously and their abrupt increase may result in impairment or deformation of important anatomical structures. Infantile hemangiomas and vascular malformations require different and individual treatments which are often multi-stage procedures carried on in specialistic centres of plastic surgery, vascular surgery or maxillofacial surgery. PMID:24979522

Wójcicki, Piotr; Wójcicka, Karolina

2014-01-01

365

Autoimmune pancreatitis mimicking Klatskin tumour on radiology.  

PubMed

Autoimmune pancreatitis (AIP) is categorised into two distinct types, AIP type 1 and 2. Although there can be multisystem involvement, rarely, the cholangitis associated with AIP can present radiologically in a manner similar to that of Klatskin tumour. We present the case of a 65-year-old man who was almost misdiagnosed with a Klatskin tumour because of the similarity in radiological features of the two aforementioned clinical entities. The patient presented with a history of jaundice, pruritus and abdominal pain, and work up showed deranged liver function tests, elevated cancer antigen 19-9 levels and positive antinuclear antibodies. CT scan of the abdomen showed findings suggestive of Klatskin tumour but due to diffuse enlargement of the pancreas and surrounding low-attenuation halo found on a closer review, a diagnosis of AIP was performed. The patient was started on standard corticosteroid therapy and responded well, with complete resolution of the radiological findings. PMID:25858920

Hadi, Yousaf Bashir; Sohail, Abdul Malik Amir Humza; Haider, Zishan

2015-01-01

366

Circulating tumour cells in breast cancer  

PubMed Central

Evaluation of isolated tumour cells in bone marrow (BM) and peripheral blood has become a major focus of translational cancer research. The presence of disseminated tumour cells in BM is a common phenomenon observed in 30–40% of primary breast cancer patients and independently predicts reduced clinical outcome. The detection of circulating tumour cells (CTCs) in blood might become a desired alternative to the invasive and painful BM biopsy. Recent clinical trials confirmed the feasibility of CTC detection as a robust and reproducible parameter for prognostication in both adjuvant and metastatic setting. The characterisation of CTCs might become an important biomarker for therapy monitoring and help to identify specific targets for novel therapeutic strategies. PMID:24066018

Krawczyk, Natalia; Banys, Malgorzata; Hartkopf, Andreas; Hagenbeck, Carsten; Melcher, Carola; Fehm, Tanja

2013-01-01

367

Sertoliform cystadenoma: a rare benign tumour of the rete testis  

PubMed Central

Abstract Sertoliform cystadenoma of the rete testis represents an uncommon benign tumour. They appear in patients from 26 to 62 years of age. We describe a case of a 66-year-old man with a tumour in the area of the epididymal head. The tumour markers were not increased. Under the assumption of a malignant testicular tumour an inguinal orchiectomy was performed. The cut surface of this tumour was of grey/white color and showed small cysts. The tumour consisted of two compartments. The epithelial like tumour cells showed a sertoliform growth pattern and cystic dilatations. In between the tumour cells repeatedly actin expressing sclerotic areas could be recognized as the second tumour component. Proliferative activity was not increased. Immunohistochemically the tumour cells were positiv for inhibin, S-100, and CD 99. Alpha feto protein (AFP), human chorionic gonadotropin (ß-HCG) and placental alkaline phosphatase (PLAP) as well as synaptophysin, epithelial membrane antigene (EMA), and BCL-2 were not expressed. As far as we know this is the sixth reported case of this tumour. Because of the benign nature of this tumour the correct diagnosis is important for the intra- and postoperative management. Here we present a case of this rare tumour and discuss potential differential diagnosis. Virtual Slides The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1956026143857335 PMID:23406299

2013-01-01

368

Primary melanoma tumour regression associated with an immune response to the tumour-associated antigen melan-A/MART-1.  

PubMed

A prediction of the theory of immunologic surveillance is that tumour antigens can be recognised by cell-mediated immunity during early development of the primary tumour by formation of tumour antigen-specific cytotoxic lymphocytes (CTLs) and that such recognition leads to destruction of those tumour cells (tumour regression) with subsequent appearance of tumour antigen-loss variants. However, this has never been shown in nonviral-induced experimental animal models of primary malignancy or in human primary cancer. We examined 2 groups of human melanoma patients where primary tumour regression was observed. Twenty-three patients with multiple (>/=3) primary melanoma showed significant histologic regression of their last tumour (median tumour regression 33%) compared to matched tumours from patients with a single primary melanoma (median 0%) (p = 0.008) or compared to their first primary tumour (median 0%) (p = 0.001). This increased regression is consistent with an "immunisation effect" seen in murine tumour transplantation studies where innoculation with >/=3 asynchronous tumours induces transplantation rejection on subsequent challenge. A significant decrease in MART-1-positive stained tumour area in the last primary tumour from multiple melanoma subjects (median 8%) vs. matched single melanoma patients (median 79%) (p = 0.004) and in the last vs. first tumour (median 76%) in multiple primary subjects was found (p = 0.008). Metastatic tumours from 17 patients whose primary skin melanomas had completely regressed (occult primary melanoma) also showed significant MART-1 tumour-loss variants (median 0% MART-1-positive tumour) compared to matched metastatic tumours from patients with nonregressing primary tumours (median 51%) (p = 0.001). A correlation with the presence of peripheral blood MART-1-specific CTLs (MHC class I-restricted IFN-gamma producing T lymphocytes) and MART-1 tumour antigen-loss variants was found (p = 0.001). Thus, in 2 groups of human melanoma subjects, we provide evidence of tumour regression associated with Melan A/MART-1 tumour antigen-loss variants correlating with formation of specific Melan A/MART-1 CTLs. PMID:11745443

Saleh, F H; Crotty, K A; Hersey, P; Menzies, S W

2001-11-01

369

Brain Autopsy  

MedlinePLUS

Brain Autopsy The Key to Understanding FTD A brain autopsy is essential to obtain a definitive diagnosis ... sense of closure. People who participate in a brain donation program should receive an autopsy report with ...

370

Brain components  

MedlinePLUS Videos and Cool Tools

The brain is composed of more than a thousand billion neurons. Specific groups of them, working in concert, provide ... of information. The 3 major components of the brain are the cerebrum, cerebellum, and brain stem. The ...

371

Brain surgery  

MedlinePLUS

Craniotomy; Surgery - brain; Neurosurgery; Craniectomy; Stereotactic craniotomy; Stereotactic brain biopsy; Endoscopic craniotomy ... cut depends on where the problem in the brain is located. The surgeon creates a hole in ...

372

Brain Malformations  

MedlinePLUS

Most brain malformations begin long before a baby is born. Something damages the developing nervous system or causes it ... medicines, infections or radiation during pregnancy interferes with brain development. Types of brain malformations include missing parts ...

373

Brain Tumors  

MedlinePLUS

... brain. Brain tumors can be benign, with no cancer cells, or malignant, with cancer cells that grow quickly. Some are primary brain ... targeted therapy. Targeted therapy uses substances that attack cancer cells without harming normal cells. Many people get ...

374

The tumour suppressor C/EBP? inhibits FBXW7 expression and promotes mammary tumour metastasis  

PubMed Central

Inflammation and hypoxia are known to promote the metastatic progression of tumours. The CCAAT/enhancer-binding protein-? (C/EBP?, CEBPD) is an inflammatory response gene and candidate tumour suppressor, but its physiological role in tumourigenesis in vivo is unknown. Here, we demonstrate a tumour suppressor function of C/EBP? using transgenic mice overexpressing the Neu/Her2/ERBB2 proto-oncogene in the mammary gland. Unexpectedly, this study also revealed that C/EBP? is necessary for efficient tumour metastasis. We show that C/EBP? is induced by hypoxia in tumours in vivo and in breast tumour cells in vitro, and that C/EBP?-deficient cells exhibit reduced glycolytic metabolism and cell viability under hypoxia. C/EBP? supports CXCR4 expression. On the other hand, C/EBP? directly inhibits expression of the tumour suppressor F-box and WD repeat-domain containing 7 gene (FBXW7, FBW7, AGO, Cdc4), encoding an F-box protein that promotes degradation of the mammalian target of rapamycin (mTOR). Consequently, C/EBP? enhances mTOR/AKT/S6K1 signalling and augments translation and activity of hypoxia-inducible factor-1? (HIF-1?), which is necessary for hypoxia adaptation. This work provides new insight into the mechanisms by which metastasis-promoting signals are induced specifically under hypoxia. PMID:21076392

Balamurugan, Kuppusamy; Wang, Ju-Ming; Tsai, Hsin-Hwa; Sharan, Shikha; Anver, Miriam; Leighty, Robert; Sterneck, Esta

2010-01-01

375

Malignant tumours of the heart: a review of tumour type, diagnosis and therapy.  

PubMed

Primary cardiac neoplasms are rare and occur less commonly than metastatic disease of the heart. In this overview, current published studies concerning malignant neoplasms of the heart are reviewed, together with some insights into their aetiology, diagnosis and management. We searched medline using the subject 'cardiac neoplasms'. We selected about 110 articles from between 1973 and 2006, of which 76 sources were used to complete the review. Sarcomas are the most common cardiac tumours and include myxosarcoma, liposarcoma, angiosarcoma, fibrosarcoma, leiomyosarcoma, osteosarcoma, synovial sarcoma, rhabdomyosarcoma, neurofibrosarcoma, malignant fibrous histiocytoma and undifferentiated sarcoma. The classic symptoms of cardiac tumours are intracardiac obstruction, signs of systemic embolisation, and systemic or constitutional symptoms. However, serious complications including stroke, myocardial infarction and even sudden death from arrhythmia may be the first signs of a tumour. Echocardiography and angiography are essential diagnostic tools for evaluating cardiac neoplasms. Computed tomography and magnetic resonance imaging studies have improved the diagnostic approach in recent decades. Successful treatment for benign cardiac tumours is usually achieved by surgical resection. Unfortunately, resection of the tumour is not always feasible. The prognosis after surgery is usually excellent in the case of benign tumours, but the prognosis of malignant tumours remains dismal. In conclusion, there are limited published data concerning cardiac neoplasms. Therefore, a high level of suspicion is required for early diagnosis. Surgery is the cornerstone of therapy. However, a multi-treatment approach, including chemotherapy, radiation as well as evolving approaches such as gene therapy, might provide a better palliative and curative result. PMID:17693068

Neragi-Miandoab, S; Kim, J; Vlahakes, G J

2007-12-01

376

Stimulation of protein synthesis in human tumours by parenteral nutrition: evidence for modulation of tumour growth.  

PubMed

Eighteen patients with localized colorectal carcinoma were randomized to receive intravenous nutrition or to be fasted during the 24 h before surgery. Protein synthesis, an index of tumour growth, was then measured by the incorporation of [13C]leucine into tumour protein immediately before surgery. The mean (s.e.m.) rate of tumour protein synthesis in patients receiving nutrition (42.7(3.5) per cent per day) was 89 per cent higher than the rate in the fasted group (22.6(1.9) per cent per day) (P = 0.002). As tumours consist of a variety of different cell types, in vitro rates of protein synthesis were measured in malignant cells isolated from colorectal tumours and cultured with autologous serum obtained from the patient in either the fasted or the fed state. There was a mean increase of 81 per cent in protein synthesis when fed rather than fasted serum was used (P less than 0.02), indicating that the malignant cells themselves respond to nutrient supply. This increase in tumour protein synthesis provides the first evidence in vivo that the exogenous supply of nutrients can modulate the rate of growth of a human tumour. PMID:1903319

Heys, S D; Park, K G; McNurlan, M A; Milne, E; Eremin, O; Wernerman, J; Keenan, R A; Garlick, P J

1991-04-01

377

Investigating citrullinated proteins in tumour cell lines  

PubMed Central

Background The conversion of arginine into citrulline, termed citrullination, has important consequences for the structure and function of proteins. Studies have found PADI4, an enzyme performing citrullination, to be highly expressed in a variety of malignant tumours and have shown that PADI4 participates in the process of tumorigenesis. However, as citrullinated proteins have not been systematically investigated in tumours, the present study aimed to identify novel citrullinated proteins in tumours by 2-D western blotting (2-D WB). Methods Two identical two-dimensional electrophoresis (2-DE) gels were prepared using extracts from ECA, H292, HeLa, HEPG2, Lovo, MCF-7, PANC-1, SGC, and SKOV3 tumour cell lines. The expression profiles on a 2-DE gel were trans-blotted to PVDF membranes, and the blots were then probed with an anti-citrulline antibody. By comparing the 2-DE profile with the parallel 2-D WB profile at a global level, protein spots with immuno-signals were collected from the second 2-DE gel and identified using mass spectrometry. Immunoprecipitation was used to verify the expression and citrullination of the targeted proteins in tumour cell lines. Results 2-D WB and mass spectrometry identified citrullinated ?-enolase (ENO1), heat shock protein 60 (HSP60), keratin 8 (KRT8), tubulin beta (TUBB), T cell receptor chain and vimentin in these cell lines. Immunoprecipitation analyses verified the expression and citrullination of ENO1, HSP60, KRT8, and TUBB in the total protein lysates of the tumour cell lines. Conclusions The citrullination of these proteins suggests a new mechanism in the tumorigenic process. PMID:24099319

2013-01-01

378

The Geneva brain collection  

PubMed Central

The University of Geneva brain collection was founded at the beginning of the 20th century. Today, it consists of 10,154 formaldehyde- or buffered formaldehyde–fixed brains obtained from the autopsies of the Department of Psychiatry and, since 1971, from the Department of Geriatrics as well. More than 100,000 paraffin-embedded blocks and 200,000 histological slides have also been collected since 1901. From the time of its creation, this collection has served as an important resource for pathological studies and clinicopathological correlations, primarily in the field of dementing illnesses and brain aging research. These materials have permitted a number of original neuropathological observations, such as the classification of Pick’s disease by Constantinidis, or the description of dyshoric angiopathy and laminar sclerosis by Morel. The large number of cases, including some very rare conditions, provides a unique resource and an opportunity for worldwide collaborations. PMID:21599692

Kövari, Enikö; Hof, Patrick R.; Bouras, Constantin

2011-01-01

379

CLASSIFICATION OF PROCEDURES INTERNATIONAL CLASSIFICATION OF DISEASES  

E-print Network

CLASSIFICATION OF PROCEDURES INTERNATIONAL CLASSIFICATION OF DISEASES 9th REVISION CLINICAL MODIFICATION 1 #12;2 #12;PREFACE This sixth edition of the International Classification of Diseases, 9th coding. The International Classification of Diseases, 9th Revision, published by the World Health

Laksanacharoen, Sathaporn

380

Duodenal bulb tumour of unknown origin  

PubMed Central

Gastrointestinal stromal tumours (GIST) are rare mesenchymal neoplasms of the gastrointestinal tract. Their development typically depends on mutations in the Kit or PDGFRA gene. We have diagnosed and treated a duodenal bulb GIST in a 63-year-old woman. The confirmation of the diagnosis was made on the basis of a histological test after radical resection of the tumour. Making the right diagnosis is crucial for patients, since complex surgical and pharmacological approaches are effective even in the advanced stages of the disease. Nevertheless, radical surgical treatment is still the primary choice for patients with GIST. PMID:25653733

Sobo?, Marcin; Szylberg, Tadeusz; Rudzi?ski, Janusz

2014-01-01

381

Thoracic Wall Reconstruction in Advanced Breast Tumours  

PubMed Central

In advanced mammary tumours, extensive resections, sometimes involving sections of the thoracic wall, are often necessary. Plastic surgery reconstruction procedures offer sufficient opportunities to cover even large thoracic wall defects. Pedicled flaps from the torso but also free flap-plasties enable, through secure defect closure, the removal of large, ulcerated, painful or bleeding tumours with moderate donor site morbidity. The impact of thoracic wall resection on the respiratory mechanism can be easily compensated for and patients? quality of life in the palliative stage of disease can often be improved. PMID:24976636

Daigeler, A.; Harati, K.; Goertz, O.; Hirsch, T.; Behr, B.; Lehnhardt, M.; Kolbenschlag, J.

2014-01-01

382

Tissue factor, angiogenesis and tumour progression  

PubMed Central

Tissue factor, the primary initiator of the coagulation cascade, maintains vascular integrity in response to injury. It is now recognised that, in addition to the role as a procoagulant activator, tissue factor participates in many tumour-related processes that contribute to malignant disease progression. The present review details the recent evidence supporting a role for tissue factor in tumour haemostasis, angiogenesis, metastasis and malignant cell survival. Furthermore, future research directions are discussed that may enhance our understanding of the role and regulation of this protein, which could ultimately lead to the innovative design and development of new anticancer therapies. PMID:18373885

Bluff, Joanne E; Brown, Nicola J; Reed, Malcolm WR; Staton, Carolyn A

2008-01-01

383

Sertoli cell tumour in an Amur tiger.  

PubMed

The histological and immunohistochemical characteristics of a malignant Sertoli cell tumour in a 17-year-old Amur tiger (Panthera tigris altaica) are described. Histological examination of the primary lesion in the right testis and metastatic lesions throughout the internal organs showed a variable cellular pattern with an admixture of tubular structures divided by fine stroma filled with fusiform to stellate cells, and sheets of polygonal cells with abundant vacuolated cytoplasm. Immunohistochemical techniques demonstrated strong positive staining for neuron-specific enolase and variable positive staining for vimentin in neoplastic cells, supporting a diagnosis of a tumour of Sertoli cell origin. PMID:11428192

Scudamore, C L; Meredith, A L

2001-01-01

384

Primate Classification  

NSDL National Science Digital Library

In this lesson students learn how classification of organisms is based on evolutionary relationships. They will also learn how primates are categorized, and how they are related. Students transfer examples (names) of primates from their location in an outline hierarchy of primate groups into a set of nested boxes reflecting that same hierarchy. A cladogram can then be drawn illustrating how these groups are related in an evolutionary way.

385

Triangle Classification  

NSDL National Science Digital Library

This geometry lesson from Illuminations presents the Triangle Classification problem. Students will attempt to classify the triangles formed in a plane when a randomly selected point is connected to the endpoints of a given line segment. Students should have access to a computer with internet access for the lesson. The material is intended for grades 9-12 and should require 1 class period to complete.

2010-12-29

386

Glomus tumour in the digit of a dog.  

PubMed

The gross and microscopical features of a glomus tumour in the digit of a 9-year-old dog are described. The tumour consisted of a red nodule near the nail of the third digit of the right forelimb and appeared painful. The tumour cells, which had round to oval hyperchromatic nuclei and scant cytoplasm, were arranged in sheets around blood vessels, or in nests or duct-like structures. This pattern has not been described previously in canine glomus tumours. Mitotic figures were seen only occasionally. Tumour cells were strongly immunolabelled for vimentin and some expressed smooth-muscle actin and desmin. They were negative for cytokeratins, neuron-specific enolase and CD34. Silver impregnation (reticulin method) stained the reticulum around blood vessels, nests of tumour cells and duct-like structures, and a delicate reticulum was seen around each tumour cell. The morphological, immunohistochemical and histochemical patterns helped in the diagnosis of this glomus tumour. PMID:12634100

Dagli, M L Z; Oloris, S C S; Xavier, J G; dos Santos, C F; Faustino, M; Oliveira, C M; Sinhorini, I L; Guerra, J L

2003-01-01

387

Tumour cell damage and leucocyte infiltration after laser immunotherapy treatment.  

PubMed

Immune response after laser-photosensitiser application could be crucial in treatment of cancers, because without it there could be no systemic, long-term tumour control. Laser immunotherapy, a novel method for treatment of metastatic tumours, uses a near-infrared laser, a laser-absorbing dye indocyanine green, and an immunoadjuvant glycated chitosan. This modality has shown an induced antitumour immune response in treatment of rat mammary metastatic tumours. The influence of this new method on the cellular structure of the tumours and on the infiltrating immune cells was studied using optical and electron microscopes. The tumour samples were examined before and immediately after the treatment for acute effects, which appeared mainly photothermal. Two weeks after treatment, significant infiltrating lymphocytes and plasma cells were found around the surviving tumour cells. These morphological findings suggest that both cell-mediated and humoral immune responses could be responsible for the observed tumour eradication and induced long-term tumour resistance. PMID:24590198

Chen, W R; Liu, H; Nordquist, J A; Nordquist, R E

2000-01-01

388

Inhibition in Multiclass Classification  

PubMed Central

The role of inhibition is investigated in a multiclass support vector machine formalism inspired by the brain structure of insects. The so-called mushroom bodies have a set of output neurons, or classification functions, that compete with each other to encode a particular input. Strongly active output neurons depress or inhibit the remaining outputs without knowing which is correct or incorrect. Accordingly, we propose to use a classification function that embodies unselective inhibition and train it in the large margin classifier framework. Inhibition leads to more robust classifiers in the sense that they perform better on larger areas of appropriate hyperparameters when assessed with leave-one-out strategies. We also show that the classifier with inhibition is a tight bound to probabilistic exponential models and is Bayes consistent for 3-class problems. These properties make this approach useful for data sets with a limited number of labeled examples. For larger data sets, there is no significant comparative advantage to other multiclass SVM approaches. PMID:22594829

Huerta, Ramón; Vembu, Shankar; Amigó, José M.; Nowotny, Thomas; Elkan, Charles

2013-01-01

389

Inhibition in multiclass classification.  

PubMed

The role of inhibition is investigated in a multiclass support vector machine formalism inspired by the brain structure of insects. The so-called mushroom bodies have a set of output neurons, or classification functions, that compete with each other to encode a particular input. Strongly active output neurons depress or inhibit the remaining outputs without knowing which is correct or incorrect. Accordingly, we propose to use a classification function that embodies unselective inhibition and train it in the large margin classifier framework. Inhibition leads to more robust classifiers in the sense that they perform better on larger areas of appropriate hyperparameters when assessed with leave-one-out strategies. We also show that the classifier with inhibition is a tight bound to probabilistic exponential models and is Bayes consistent for 3-class problems. These properties make this approach useful for data sets with a limited number of labeled examples. For larger data sets, there is no significant comparative advantage to other multiclass SVM approaches. PMID:22594829

Huerta, Ramón; Vembu, Shankar; Amigó, José M; Nowotny, Thomas; Elkan, Charles

2012-09-01

390

Inter-hemispheric language functional reorganization in low-grade glioma patients after tumour surgery.  

PubMed

Despite many claims of functional reorganization following tumour surgery, empirical studies that investigate changes in functional activation patterns are rare. This study investigates whether functional recovery following surgical treatment in patients with a low-grade glioma in the left hemisphere is linked to inter-hemispheric reorganization. Based on literature, we hypothesized that reorganization would induce changes in the spatial pattern of activation specifically in tumour homologue brain areas in the healthy right hemisphere. An experimental group (EG) of 14 patients with a glioma in the left hemisphere near language related brain areas, and a control group of 6 patients with a glioma in the right, non-language dominant hemisphere were scanned before and after resection. In addition, an age and gender matched second control group of 18 healthy volunteers was scanned twice. A verb generation task was used to map language related areas and a novel technique was used for data analysis. Contrary to our hypothesis, we found that functional recovery following surgery of low-grade gliomas cannot be linked to functional reorganization in language homologue brain areas in the healthy, right hemisphere. Although elevated changes in the activation pattern were found in patients after surgery, these were largest in brain areas in proximity to the surgical resection, and were very similar to the spatial pattern of the brain shift following surgery. This suggests that the apparent perilesional functional reorganization is mostly caused by the brain shift as a consequence of surgery. Perilesional functional reorganization can however not be excluded. The study suggests that language recovery after transient post-surgical language deficits involves recovery of functioning of the presurgical language system. PMID:25500538

Kristo, Gert; Raemaekers, Mathijs; Rutten, Geert-Jan; de Gelder, Beatrice; Ramsey, Nick F

2015-03-01

391

[Morbidity of the tumours of the sphere head and neck in Bamako].  

PubMed

This work reports the results of one year (November 2004-October 2005) descriptive study of tumours located in the head and neck areas in the ENT department of the University-Hospital of Gabriel Toure in Bamako. Were included in the study patients whose files showed epidemiology data: age, sex, profession, residence and period of the medical checking, and exposition factors: anatomic location, results of histology and image data of the tumours. Where excluded from the study the patients whose file were not completed and those that have had eye and brain tumours From the data base of the department, a total of 60 cases of tumours were monitored and 25 others cases were excluded according to the criteria. Among the 60 cases, 24 tumours (40%) were malign and 36 were benign. Goiter was the most found benign tumor according to the results of the hystology analysis. In most cases (15 out of 36, 41.67%) the histology analysis showed an colloid adenoma Other rare tumors like rhinoscleroma (5 cases out of 36, 13.89%), nose invertus papilloma (2 cases out of 36, 5.55%) where found. These were easily diagnosed and treated. In the group of malign tumors, the pharyngolaryngeal cancer was the most found (11 cases out of 24) and the most predominant histology of these cancers was the epidermoid carcinoma. Two of these cancers were found in patients below fifteen years of age, but no other risk factors like expositions was noted in the files of these two patients. Other malign tumors have been found: nose and sinusal cancers and thyroid carcinoma. In most cases these tumors were diagnosed at an advanced stage. PMID:20093222

Keita, M; Kampo, M I; Timbo, S K; Traoré, C B; Diallo, M; Doumbia-Singaré, K; Ag Mohamed, A

2009-01-01

392

Morphological approach to tumours of the testis and paratestis  

PubMed Central

Most neoplastic scrotal masses ultimately prove to be germ cell tumours and are recognisable with routine haematoxylin and eosin?stained sections. The differential diagnosis may be focused, even before reviewing histological sections, by knowledge of patient age, medical history, tumour site (testicular vs paratesticular) and gross findings. Some cases may prove to be diagnostically challenging, including rare tumours, a common tumour with an unusual pattern, a metastatic tumour, or a neoplasm with features that mimic another tumour. Several morphological patterns are seen with some frequency and these generate recurring sets of differential diagnostic considerations. These common patterns include testicular tumours with a predominant diffuse arrangement of cells with pale to clear cytoplasm, tumours with a glandular/tubular pattern, tumours with a microcystic pattern and tumours composed of oxyphilic cells. Intratubular proliferations of atypical cells, paratesticular glandular and/or papillary tumours, or tumours with spindle cell morphology can also be challenging to diagnose correctly. In some problematic cases, immunohistochemical staining may be useful to resolve these differential diagnoses. PMID:17307866

Emerson, Robert E; Ulbright, Thomas M

2007-01-01

393

Merkel cell carcinoma: a malignant neuroendocrine tumour of the eyelid.  

PubMed Central

Merkel cell carcinoma is a recently described tumour which may occur on the face of the elderly. We report such a lesion which presented as a cyst on the eyelid of an 88-year-old woman. This tumour differs from other tumours of the eyelids in its propensity for local and distant spread. Images PMID:6882717

Kirkham, N; Cole, M D

1983-01-01

394

RESEARCH ARTICLE Open Access Adaptation to statins restricts human tumour  

E-print Network

RESEARCH ARTICLE Open Access Adaptation to statins restricts human tumour growth in Nude mice Julie to tumours in Nude mice. Methods: HGT-1 human gastric cancer cells and L50 statin-resistant derivatives were injected subcutaneously into Nude mice and tumour growth was recorded. At the end of the experiment

Paris-Sud XI, Université de

395

Allelic loss of 10q23, the PTEN tumour suppressor gene locus, in Barrett's oesophagus-associated adenocarcinoma  

PubMed Central

PTEN is a putative tumour suppressor gene located on chromosome band 10q23. Mutations in PTEN have been identified in numerous human malignancies, including cancers of the brain, endometrium, ovary, and prostate. In this study, we screened 80 Barrett's oesophagus-associated adenocarcinomas (BOAd) for loss of heterozygosity (LOH) at 10q23, using the microsatellite markers D10S541, D10S219, and D10S551. Tumours demonstrating LOH were then screened for the presence or absence of PTEN mutations. LOH at one or more loci was identified in 17/80 (21%) cases. In none of these cases did we detect mutations in PTEN. The presence of LOH did not correlate with patient age, tumour stage, degree of differentiation, presence of perineural or vascular invasion, or overall survival. We conclude that LOH at chromosome 10q23 is uncommon in BOAd, is not associated with mutations in the PTEN tumour suppressor gene, and does not correlate with the clinical or pathologic features of these tumours. It is possible that PTEN is inactivated through other mechanisms in BOAd. © 2001 Cancer Research Campaign http://www.bjcancer.com PMID:11259087

Kulke, M H; Odze, R D; Thakore, K S; Thomas, G; Wang, H; Loda, M; Eng, C

2001-01-01

396

Positron emission tomography for urological tumours.  

PubMed

For urological tumours, positron emission tomography (PET) is currently most useful in testicular cancer. In patients with residual masses or raised marker levels after treatment, PET is both sensitive and specific for detecting recurrent disease, at suspected and unsuspected sites. Although fewer studies are available it also appears to be useful for staging at diagnosis, although this requires further investigation. Prostate cancer imaging has been more variable, with studies showing that PET cannot reliably differentiate between tumour and hypertrophy. It is not as good as a bone scan for defining bone metastases. In renal cancer, PET can be used to define the primary tumour, providing better staging of local recurrence than computed tomography (CT), and to define metastatic disease. There are few studies in bladder cancer, and despite excretion of the tracer via the bladder in early studies, it has better results than CT or magnetic resonance imaging for local staging; again it can detect metastases. Overall, the place of PET in urological tumours is developing, with the strongest areas undoubtedly being testicular and renal cancer. Tracers other than fluorodeoxyglucose are being examined and are providing further information. PMID:12823366

Hain, S F; Maisey, M N

2003-07-01

397

Coordinated regulation of myeloid cells by tumours  

Microsoft Academic Search

Myeloid cells are the most abundant nucleated haematopoietic cells in the human body and are a collection of distinct cell populations with many diverse functions. The three groups of terminally differentiated myeloid cells — macrophages, dendritic cells and granulocytes — are essential for the normal function of both the innate and adaptive immune systems. Mounting evidence indicates that the tumour

Dmitry I. Gabrilovich; Suzanne Ostrand-Rosenberg; Vincenzo Bronte

2012-01-01

398

Targeting tumours with genetically enhanced T lymphocytes  

Microsoft Academic Search

The genetic modification of T lymphocytes is an important approach to investigating normal T-cell biology and to increasing antitumour immunity. A number of genetic strategies aim to increase the recognition of tumour antigens, enhance antitumour activities and prevent T-cell malfunction. T cells can also be engineered to increase safety, as well as to express markers that can be tracked by

Isabelle Rivière; Renier Brentjens; Michel Sadelain

2003-01-01

399

In vivo evaluation of intracellular drug-nanocarriers infused into intracranial tumours by convection-enhanced delivery: distribution and radiosensitisation efficacy  

Microsoft Academic Search

The objective of the present study was to investigate the interest of convection-enhanced delivery (CED) for the administration\\u000a of a nanocarrier-based radiosensitizing chemotherapy in the rat brain. Pursuing on newly developed lipid nanocapsules (LNC)\\u000a that can be internalised within brain tumour cells, we studied their intracerebral distribution when labelled with fluorescent\\u000a Nile red (NR). As paclitaxel (Px) represents an interesting

Sandrine Vinchon-Petit; Delphine Jarnet; Archibald Paillard; Jean-Pierre Benoit; Emmanuel Garcion; Philippe Menei

2010-01-01

400

AN ANTIBODY FOR MACROPHAGE MIGRATION INHIBITORY FACTOR SUPPRESSES TUMOUR GROWTH AND INHIBITS TUMOUR-ASSOCIATED ANGIOGENESIS  

Microsoft Academic Search

To verify the role of macrophage migration inhibitory factor (MIF) in tumourigenesis, we examined the effect of an anti-MIF antibody on tumour growth and angiogenesis. We inoculated murine colon adenocarcinoma cell line colon 26 cells subcutaneously into the flank in BALB\\/c mice. After nine days, we treated tumour-bearing mice with an anti-rat MIF antibody by intraperitoneal injection on days 9,

Hideaki Ogawa; Jun Nishihira; Yuji Sato; Masao Kondo; Norihiko Takahashi; Takahiro Oshima; Satoru Todo

2000-01-01

401

DNA profile and tumour progression in patients with superfical bladder tumours  

Microsoft Academic Search

229 patients with Grade 1–2 tumours (WHO), all category Ta or T1 (UICC) and surgically treated, were followed clinically and by flowcytofluorometric DNA-analysis (FCM). The tumours were characterised by their DNA profile. 175 cases were found to be diploid and fiftyfour cases showed aneuploidy. The mean follow-up time with continous FCM analysis was 2.6 years. During this period 19 patients

H. Gustafson; B. Tribukait; P. L. Esposti

1982-01-01

402

Tumour angiogenesis in Epstein-Barr virus-associated post-transplant smooth muscle tumours.  

PubMed

Epstein-Barr virus (EBV)-associated post-transplant smooth muscle tumours (PTSMT), are rare complications following organ/stem cell transplantation. Despite the mainly benign behaviour of PTSMT, alternative therapies are needed for those patients with progressive tumours. In tumours not approachable by surgery or reduction of immunosuppression, the angiogenic microenvironment might be a potential target of therapy, an approach that is well utilised in other soft tissue neoplasms. In a previous study, we evaluated the expression of EBV-related genes and the microRNA profile in PTSMT, but so far the characteristics of angiogenesis in PTSMT are not known. Therefore, the aim of this study was to evaluate the expression pattern of angiogenesis-related genes in PTSMT, in order to identify potential target molecules for anti-angiogenic therapy.PTSMT (n?=?5 tumours) were compared with uterine leiomyomas (n?=?7). Analyses included real-time PCR of 45 angiogenesis-associated genes, immunohistochemistry (CD31, prostaglandin endoperoxide synthase 1/PTGS1) and assessment of tumour vascularisation by conventional histopathology.PTSMT showed similar or fewer vessels than leiomyomas. Of the genes under investigation, 23 were down-deregulated (pro-angiogenic and some anti-angiogenic factors) and five were up-regulated (e.g. PTGS1 which is expressed at very low levels in leiomyomas but moderately higher levels in PTSMT).In summary, no particular target molecule could be identified, because tumour angiogenesis in PTSMT is characterised by low levels of major pro-angiogenic factors and there is no prominent increase in tumour vascularisation. EBV can induce angiogenesis via its viral late membrane protein 1 (LMP1) but PTSMT frequently do not express LMP1, which could be an explanation why, despite EBV infection, PTSMT show no exaggerated tumour angiogenesis. PMID:24398114

Jonigk, Danny; Izykowski, Nicole; Maegel, Lavinia; Schormann, Eileen; Ludewig, Britta; Kreipe, Hans; Hussein, Kais

2014-01-01

403

Granulosa-theca cell tumour of the ovaries. A late metastasizing tumour.  

PubMed

Granulosa-theca cell tumours are ovarian neoplasms of low malignancy with hormone secreting potential, accounting for 2-3% of all ovarian cancers. They have an uncertain clinical course and a potential for late recurrence after surgical removal. Clinical features of a patient presenting with pulmonary metastases 21 years after removal of the primary tumour are described, along with a review of the management options. PMID:10375991

Spencer, H W; Mullings, A M; Char, G; Carpenter, R

1999-03-01

404

Tumour angiogenesis in Epstein-Barr virus-associated post-transplant smooth muscle tumours  

PubMed Central

Epstein-Barr virus (EBV)-associated post-transplant smooth muscle tumours (PTSMT), are rare complications following organ/stem cell transplantation. Despite the mainly benign behaviour of PTSMT, alternative therapies are needed for those patients with progressive tumours. In tumours not approachable by surgery or reduction of immunosuppression, the angiogenic microenvironment might be a potential target of therapy, an approach that is well utilised in other soft tissue neoplasms. In a previous study, we evaluated the expression of EBV-related genes and the microRNA profile in PTSMT, but so far the characteristics of angiogenesis in PTSMT are not known. Therefore, the aim of this study was to evaluate the expression pattern of angiogenesis-related genes in PTSMT, in order to identify potential target molecules for anti-angiogenic therapy. PTSMT (n?=?5 tumours) were compared with uterine leiomyomas (n?=?7). Analyses included real-time PCR of 45 angiogenesis-associated genes, immunohistochemistry (CD31, prostaglandin endoperoxide synthase 1/PTGS1) and assessment of tumour vascularisation by conventional histopathology. PTSMT showed similar or fewer vessels than leiomyomas. Of the genes under investigation, 23 were down-deregulated (pro-angiogenic and some anti-angiogenic factors) and five were up-regulated (e.g. PTGS1 which is expressed at very low levels in leiomyomas but moderately higher levels in PTSMT). In summary, no particular target molecule could be identified, because tumour angiogenesis in PTSMT is characterised by low levels of major pro-angiogenic factors and there is no prominent increase in tumour vascularisation. EBV can induce angiogenesis via its viral late membrane protein 1 (LMP1) but PTSMT frequently do not express LMP1, which could be an explanation why, despite EBV infection, PTSMT show no exaggerated tumour angiogenesis. PMID:24398114

2014-01-01

405

Ensemble sparse classification of Alzheimer's disease.  

PubMed

The high-dimensional pattern classification methods, e.g., support vector machines (SVM), have been widely investigated for analysis of structural and functional brain images (such as magnetic resonance imaging (MRI)) to assist the diagnosis of Alzheimer's disease (AD) including its prodromal stage, i.e., mild cognitive impairment (MCI). Most existing classification methods extract features from neuroimaging data and then construct a single classifier to perform classification. However, due to noise and small sample size of neuroimaging data, it is challenging to train only a global classifier that can be robust enough to achieve good classification performance. In this paper, instead of building a single global classifier, we propose a local patch-based subspace ensemble method which builds multiple individual classifiers based on different subsets of local patches and then combines them for more accurate and robust classification. Specifically, to capture the local spatial consistency, each brain image is partitioned into a number of local patches and a subset of patches is randomly selected from the patch pool to build a weak classifier. Here, the sparse representation-based classifier (SRC) method, which has shown to be effective for classification of image data (e.g., face), is used to construct each weak classifier. Then, multiple weak classifiers are combined to make the final decision. We evaluate our method on 652 subjects (including 198 AD patients, 225 MCI and 229 normal controls) from Alzheimer's Disease Neuroimaging Initiative (ADNI) database using MR images. The experimental results show that our method achieves an accuracy of 90.8% and an area under the ROC curve (AUC) of 94.86% for AD classification and an accuracy of 87.85% and an AUC of 92.90% for MCI classification, respectively, demonstrating a very promising performance of our method compared with the state-of-the-art methods for AD/MCI classification using MR images. PMID:22270352

Liu, Manhua; Zhang, Daoqiang; Shen, Dinggang

2012-04-01

406

Multiple endocrine neoplasias in a dog: corticotrophic tumour, bilateral adrenocortical tumours, and pheochromocytoma.  

PubMed

In a 10-year-old ovariohysterectomized standard Schnauzer, the finding of dexamethasone-resistant hypersecretion of cortisol, the results of computed tomography, and elevated plasma concentrations of ACTH suggested the presence of both adrenocortical tumour and pituitary-dependent hyperadrenocorticism. The dog made an uneventful recovery after bilateral adrenalectomy and remained in good health for 31/2 years with substitution for the induced hypoadrenocorticism. Then the enlarged pituitary caused neurological signs and eventually euthanasia was performed. The surgically excised right adrenal contained a well-circumscribed tumour of differentiated adrenocortical tissue and in the left adrenal there were two adrenocortical tumours and a pheochromocytoma. The unaffected parts of the adrenal cortices were well developed and without regressive transformation. At necropsy there were no metastatic lesions. The cells of the pituitary tumour were immunopositive for ACTH and had characteristics of malignancy. The present combination of corticotrophic tumour, adrenocortical tumours, and pheochromocytoma may be called 'multiple endocrine neoplasia' (MEN), but does not correspond to the inherited combinations of diseases known in humans as the MEN-1 and the MEN-2 syndromes. It is suggested that the co-existence of hyperadrenocorticism and pheochromocytoma may be related to the vascular supply of the adrenals. Some chromaffin cells of the adrenal medulla are directly exposed to cortical venous blood, and intra-adrenal cortisol is known to stimulate catecholamine synthesis and may promote adrenal medullary hyperplasia or neoplasia. PMID:9563161

Thuróczy, J; van Sluijs, F J; Kooistra, H S; Voorhout, G; Mol, J A; van der Linde-Sipman, J S; Rijnberk, A

1998-04-01

407

Soft tissue giant cell tumour of low malignant potential: a rare tumour at a rare site.  

PubMed

"Soft tissue giant cell tumour of low malignant potential" is considered as the soft tissue counterpart of osteoclastoma of the bone. It is a primary soft tissue tumour which is classified under the category of fibrohistiocytic tumours of intermediate malignancy.Seventy percent of the tumours involve the extremities and only about seven percent of them arise in head and neck region. They are composed of nodules of histiocytes in a vascular stroma, with multinucleated osteoclast-like giant cells positive for vimentin, smooth muscle actin (SMA), CD68 and Tarterate Resistant Acid Phosphatase (TRAP). We are presenting a case of a 75-year-old man who had a nodule on the ala of the nose. Histopathology showed a histiocytic lesion. Benign fibrous histiocytoma, plexiform fibrohistiocytic tumour, solitary reticulohistiocytoma and histioid leprosy were ruled out by using special stains and immunostains. Expression of smooth muscle actin and CD68 confirmed the diagnosis of a soft tissue giant cell tumour with a low malignant potential. PMID:24551690

Bhat, Amoolya; V, Geethamani; C, Vijaya

2013-12-01

408

Brain Explorer  

NSDL National Science Digital Library

Brain Explorer is an educational Web site from the Lundbeck Institute that provides a highly visual and informative tour of the brain. Brain Atlas offers a good starting point, with well-designed diagrams of the brain and spinal cord, detailed explanatory information, and a handy pop-up glossary (which contains great graphics of its own). The section titled Neurological Control describes neuron structure and function. Other features include a section on brain