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At least 1,153 records · Page 64Linked to original sources
PubMed2003

Improved sensitivity of T-cell clonality detection in mycosis fungoides by hand microdissection and heteroduplex analysis.

BACKGROUND: The presence of a dominant T-cell clone is an important diagnostic criterion in cutaneous T-cell lymphomas (CTCLs) and in atypical T-cell cutaneous infiltrates. Procedures based on polymerase chain reaction (PCR) are the most sensitive to detect clonality, but heteroduplex analysis is less sensitive than other methods such as denaturing gradient gel electrophoresis. OBJECTIVE: To assess whether a gross hand microdissection of the superficial (papillary) portion of the dermal infiltrate may improve the sensitivity of T-cell clonality detection by PCR-heteroduplex analysis in CTCL. SETTING: Regional university hospital (secondary or tertiary referral center). Patients A total of 29 patients with a definite diagnosis of mycosis fungoides based on typical histologic and immunophenotypic features were selected with patch (16) or plaque (13) stages. MAIN OUTCOME MEASURES: Assessment of T-cell clonality by PCR amplification of the T-cell receptor gamma chain followed by heteroduplex analysis using DNA extracted from the entire biopsy specimen and after gross microdissection of the subepidermal bandlike dermal infiltrate. RESULTS: T-cell clonality was demonstrated in 24 of 29 cases when hand microdissection was used compared with 16 of 29 cases with DNA analysis from entire biopsy specimens; thus, hand microdissection resulted in a sensitivity improvement of approximatively 50%. CONCLUSIONS: Hand microdissection substantially improves the detection of a T-cell clone in CTCL when using a PCR-heteroduplex analysis and could be used routinely in the clinical evaluation of T-cell infiltrates. Importantly, the microdissection method was found to be more useful for the detection of T-cell clones in early patch stages of CTCL than in plaque-stage disease.

Clone Cells↗
PubMed2005

Microsatellite instability and alterations of mismatch repair protein expression in choroidal melanomas.

OBJECTIVES: To examine choroidal melanomas for genomic instability, manifested by microsatellite instability (MSI) and mismatch repair (MMR) protein alterations, and to determine the association of these alterations with selected clinicopathological features of the tumors. METHODS: Polymerase chain reaction-based microsatellite assays were applied to analyze 57 cases of choroidal melanomas using 11 microsatellite markers at 5 chromosomal regions: 1p, 2p, 4q, 9p, and 17p. Immunoperoxidase staining methods and mouse monoclonal antibodies were used to investigate the expression patterns of MMR proteins. RESULTS: Microsatellite instability was found at the 1p, 9p, and 17p regions in these lesions with an overall prevalence of 35% (20/57). The frequency of MSI ranged from 9% (1/11) to 27% (3/11), ie, low-level MSI (MSI-L). The instability was most commonly found at the 1p region (D1S2734, 55%; D1S2832, 40%; and D1S233, 20%). Two MSI banding patterns, band shifts and the appearance of additional bands, were found in 10% and 90% of the unstable lesions, respectively. The average percentages of hMLH1 and hMSH2 positively stained cells were insignificantly reduced in the unstable lesions (81.7 +/- 9.3 and 76.7 +/- 16.7) as compared with the stable lesions (84.1 +/- 15.5 and 78.6 +/- 19.6; P = .62 and 0.74 for hMLH1 and hMSH2, respectively). There was no significant difference in survival between the 2 groups; however, relative to the stable subset, the unstable tumors showed a trend (P<.10) toward occurring at a younger age and having tumor cells in vascular lakes. CONCLUSIONS: The presence of MSI-L in some choroidal melanomas defines a novel genetic subset of these tumors and suggests that MSI (genomic instability) may play a role in their molecular pathogenesis. Elucidation of the underlying mechanisms for MSI will require further investigation. CLINICAL RELEVANCE: Detection of the MSI-L pattern might prove to be useful as an adjunct to the conventional diagnosis of choroidal melanomas. Larger series are needed to determine whether any of the correlative trends noted in this study will achieve statistical significance. To the best of our knowledge, this study is the first to define both the MSI and MMR protein expression features of choroidal melanomas.

Base Pair Mismatch↗
PubMed1999

Psychological characteristics of candidates for liver transplantation: differences according to history of substance abuse and UNOS listing. United Network for Organ Sharing.

Liver transplantation for patients with a history of substance abuse remains controversial. Resumption of heavy alcohol use postoperatively is a threat to long-term survival, but recidivism among transplanted alcoholics is reportedly low. An argument against psychological evaluation prior to transplantation revolves around the speculation that candidates will attempt to portray themselves as more desirable prior to listing with UNOS (United Network for Organ Sharing). This study measured psychological distress, coping styles, optimism, selected personality features, and perception of family environment among 73 U.S. military veterans who were candidates for liver transplantation. Candidates with positive histories of substance abuse revealed significantly more distress, less adaptive coping styles, and more character pathology than their counterparts. The only significant difference according to UNOS listing was on one measure of family environment. Results support preoperative psychological assessment and intervention on a more extensive level for substance abusers and raise questions for future research.

Adaptation, Psychological↗
PubMed1988

Embryonal carcinoma of the testis.

Long-term survival rates were correlated with selected clinical features in 479 patients with embryonal carcinoma of the testis and 33 patients with endodermal sinus tumor (infantile embryonal carcinoma, yolk sac tumor). In the period 1977 to 1982 embryonal carcinoma accounted for 26.8% of newly diagnosed germ cell tumors and 43% of nonseminomatous germ cell tumors entered in the Centralized Cancer Patient Data System. Among patients with embryonal carcinoma, over 80% were diagnosed in the 15-to-34 year age group. Seventy-four percent of the patients had metastatic disease at the time of diagnosis, and 50% of these had distant metastases, attesting to the aggressiveness of embryonal carcinoma and its tendency to early hematogenous spread. Despite the highly malignant nature of the tumor, the overall 5-year survival rate with treatments used was an excellent, 88%. Survival was correlated with the extent of disease at the time of diagnosis; the 5-year actuarial survival rates for patients with localized, regional, and distant disease were 98%, 96%, and 74%, respectively. Endodermal sinus tumor was uncommon (1.8% of all testicular germ cell tumors), occurred predominantly in the younger age group (0-24 years), and in 50% of the cases was localized to the testis. The survival rate for the 33 patients with this form of tumor was slightly worse than for the "adult form" of embryonal carcinoma. The authors conclude that survival of patients with embryonal carcinoma has greatly improved over the last decade as a result of improved methods for early detection of metastatic deposits and the effectiveness of newer chemotherapies in the treatment of disseminated disease.

Age Factors↗
PubMed1995

Characterization of malignant colon tumors with 31P nuclear magnetic resonance phospholipid and phosphatic metabolite profiles.

BACKGROUND: To further characterize selected pathologic features on a biochemical level, the authors analyzed the nuclear magnetic resonance metabolite and phospholipid spectra of 30 malignant colon tumors using 31P magnetic resonance spectroscopy. METHODS: Eleven individual generic phospholipids were identified in the spectra of 17 phospholipid extracts, and 31 individual phosphatic metabolites were identified in the spectra of 13 perchloric acid extracts. The metabolites and lipids were quantified for statistical intergroup comparisons based on tumor stage, lymph node status, differentiation, mucin production, blood vessel invasion (BVI), and lymphatic vessel invasion (LVI). RESULTS: Significant elevations in the relative concentration of alpha-glycerol phosphate were noted when comparing AJCC tumor classification (T3 vs. T2, 0.92 +/- 0.14 vs. 0.46 +/- 0.11, P < 0.009), tumor differentiation (moderately vs. well differentiated, 0.92 +/- 0.14 vs. 0.46 +/- 0.11, P < 0.009), and BVI (presence vs. absence, 1.03 +/- 0.04 vs. 0.68 +/- 0.10, P < 0.028) by elastic tissue stain. Among the tissue phospholipids analyzed, the relative concentration of a choline phospholipid was significantly different when comparing moderately and poorly differentiated tumors (6.26 +/- 0.56 vs. 3.29 +/- 0.30, P < 0.001), T2 and T3 tumors (3.90 +/- 0.45 vs. 6.31 +/- 0.56, P < 0.009), and mucin-positive vs. mucin-negative tumors (4.46 +/- 0.56 vs. 6.83 +/- 0.76, P < 0.028). Differences in lymph node status of the cases analyzed in this study (lymph node positive vs. lymph node negative) were noted for tumors with elevated levels of sphingomyelin (8.13 +/- 0.40 vs. 6.88 +/- 0.16, P < 0.02), diminished levels of phosphatidylinositol (5.25 +/- 0.27 vs. 6.38 +/- 0.34, P < 0.02), elevated levels of beta-glycerol phosphate (5.30 +/- 0.70 vs. 1.20 +/- 0.06, P < 0.05), and elevated levels of glycerol 3-phosphoserine (0.48 +/- 0.01 vs. 0.23 +/- 0.02, P < 0.002). CONCLUSIONS: The characteristic differences in the phospholipid and intermediate phosphate metabolite profiles identified through magnetic resonance spectroscopic and histopathologic analysis may provide important information regarding the nature of tumor and cell membrane metabolism. Differences in these profiles may identify markers useful for biologic behavior, provide prognostic information, and characterize the impact of the pathologic features of colon cancer.

Cell Differentiation↗
PubMed2000

Advances in research on the fragile X syndrome.

Fragile X syndrome is a neurodevelopmental disorder that results from a single gene mutation on the X chromosome. The purpose of this review is to summarize key advances made in understanding the fragile X premutation gene seen in carriers and the full mutation gene seen in persons with the syndrome. DNA testing has replaced cytogenetic testing as the primary method for identification of fragile X, although the efficacy of protein level screening is being explored. The premutation is associated with no effects, although there is evidence of physical effects-primarily premature menopause and mild outward features of the fragile X syndrome-among premutation carriers. There is much controversy regarding premutation effects on psychological development. The few experimental studies carried out to date do not suggest noticeable or significant effects. One challenge in addressing this controversy is the sometimes ambiguous differentiation between premutation and full mutation genes. There is a well-established yet highly variable phenotype of the full mutation. Research from this decade has helped to address specific aspects of this phenotype, including the early course of its development in males, the influence of home and family environments, the nature of social difficulties and autistic features seen in boys and girls with fragile X, and the potential role of hyperarousal or hyper-reactivity. Studies in these areas, and on the role of FMR protein, will contribute towards ongoing advances in our understanding of fragile X syndrome and its mechanisms. The variability in physical, social, and cognitive features, as described in this review, is one that prohibits clear-cut screening guidelines designed to avoid high rates of both false positives and false negatives. Results from recent studies indicate the need to consider behavioral features in selecting candidates for fragile X screening. MRDD Research Reviews 2000;6:96-106.

Cognition↗
PubMed1985

Amyotrophic lateral sclerosis: Part 2. Etiopathogenesis.

The pathogenesis of the motor neuronal degeneration in amyotrophic lateral sclerosis (ALS) is unclear, though several possible etiological factors are currently being investigated. A unifying hypothesis will have to explain the diverse geographical occurrence, clinical features, and selective vulnerability and relative resistance of different neuronal populations in the disease. It is possible that different biochemical defects underlie this diversity, or alternatively that the many factors incriminated in the etiology may act upon an underlying genetic-biochemical abnormality to trigger premature neuronal death. Viruses, metals, endogenous toxins, immune dysfunction, endocrine abnormalities, impaired DNA repair, altered axonal transport, and trauma have all been etiologically linked with ALS, but convincing research evidence of a causative role for any of these factors is yet to be demonstrated.

Aged↗
PubMed1984

On the maturation rate of the neutrophil.

Fifty-three maturing bone marrow cells of the granulocyte cell series stained with Giemsa stain and magnified 1,000 times were scanned by a "computerized microscope" consisting of a LSI-11/23 microprocessor and a black-and-white video camera attached to a "frame grabber ." Each sampled cell was digitized into 70 X 70 pixels, each pixel representing 0.04 micron of the real image. The pixel gray values ranged between 0 and 255. Zero stood for white, 255 represented black, while the numbers in between stood for the various shades of gray. The cells represented six different stages of granulocytic maturation: myeloblast, promyelocyte, myelocyte, metamyelocyte , band form, and polymorphonuclear granulocyte. A discriminant analysis program selected 19 features best distinguishing between the six different cell types and computed five canonical discriminant functions defining a Space in which maturation was studied. In the Space, distance between two cells serves as a measure of similarity. The closer two cells are, the more similar they are and vice versa. This measure was applied here to express the degree of similarity between the neutrophil maturation classes, and since they represent states in the neutrophil life history, it is applicable also as a yardstick for the quantitation of differentiation. In the Space, the life history of a cell is represented by a trajectory originating in the myeloblast and terminating in the granulocyte state. Displacement along the trajectory represents cell maturation that is expressed relatively to the least differentiated state of the myeloblast. The further a cell from this state the more mature it is. The same yardstick also serves for differentiation rate estimates represented in the Space by displacement velocities that are derived from the known "transit times" of a cell in each state. The methodology is also applied for cell production estimates. Unlike other "computerized microscopes" serving for cell classification, the instrument described in this study is primarily a cell-comparator providing a precise measure of similarity between any two cells.

Bone Marrow Cells↗
PubMed2002

Metabolic characterization of childhood brain tumors: comparison of 18F-fluorodeoxyglucose and 11C-methionine positron emission tomography.

BACKGROUND: Positron emission tomography (PET) scans of primary brain tumors were performed in pediatric patients to examine whether metabolic characteristics could be used as an index of clinical aggressiveness. METHODS: Twenty-seven pediatric patients with untreated primary central nervous system neoplasms were studied with PET scans using 2-[(18)F] fluoro-2-deoxy-D-glucose (FDG) and/or L-[methyl-(11)C] methionine (MET). Metabolic characteristics as assessed with FDG and MET standardized uptake values (SUV) and SUV-to-normal brain ratios were compared with histopathology and selected histochemical features such as proliferation activity (Ki-67(MIB-1)) and apoptotic, vascular, and cell density indices. The median followup time was 43 months. RESULTS: The accumulation of both FDG and MET was significantly higher in high-grade than in low-grade tumors, but a considerable overlap was found. The accumulation of both tracers was associated positively with age. High-grade tumors showed higher proliferative activity and vascularity than the low-grade tumors. In univariate analysis, FDG-PET, MET-PET, and apoptotic index were independent predictors of event-free survival. CONCLUSION: We found that both FDG and MET uptake in pediatric brain tumors are associated with malignancy grade. However, no clear limits of SUVs and SUV-to-normal brain ratios can be set between low-grade and high-grade tumors, which makes the assessment of malignancy grade using metabolic imaging with PET scan difficult in individual cases. Although FDG-PET and MET-PET do not compensate for histopathologic evaluation, they may give valuable additional information especially if invasive procedures to obtain histopathologic samples are not feasible.

Adolescent↗
PubMed1982

Discrimination of G1, S, and G2 cells using high-resolution TV-scanning and multivariate analysis methods.

Images of exponentially growing mouse L fibroblasts were used to test whether G1, S, and G2 cells could be discriminated by means of densitometric, geometric, textural and chromatin features. The cells were preincubated with FUdR and labeled with 3H-TdR. The definition of G1, S, and G2 was based on autoradiography used to define labeled S cells, and DNA content used to define unlabeled 2c (G1) and 4c (G2) cells. The methanol-fixed Feulgen-stained nuclei were scanned with a TV Plumbicon camera equipped with an array-processor system. Thirty-one nuclear features were calculated and stored together with the precise coordinates of each cell for later relocation and correlation with the autoradiographic data. The features were geometric, densitometric, textural and chromatin parameters of the Feulgen stained images. Feature evaluation and supervised learning were performed. When DNA content was excluded 14 textural and chromatin features were selected. By using these a correct classification of about 80% was achieved. Inclusion of DNA content and its correlates caused degeneration of performance, yielding 75% correct classification. DNA content alone gave 69% correct classification.

Animals↗
PubMed2004

Metastatic malignant melanoma in liver aspirate: cytomorphologic distinction from hepatocellular carcinoma.

Hepatic metastases of malignant melanoma are not unusual and frequently occur with a clinically long latent period following resection of a cutaneous or ocular primary. Due to its overlapping cytomorphology with a primary hepatocellular carcinoma, diagnostic difficulties may arise on fine-needle aspiration of these lesions if the clinical history of melanoma is not known. Thirty-two cases of metastatic melanoma in the liver and primary hepatocellular carcinoma were studied. Aspiration was performed under ultrasound guidance using 22-gauge spinal needle. Slides were stained with Diff-Quik and Papanicolaou stain; cell blocks were stained with H&E. A panel of immunostains was performed using conventional methodology. Of the 12 cytologic parameters assessed, the most helpful in making a metastatic melanoma diagnosis were the presence of sheet-like architecture, plasmacytoid and/or biphasic (epithelioid/spindled cell) morphology, cytoplasmic tails, necrosis, and cytoplasmic melanin-like pigment. For hepatocellular carcinoma, the presence of trabeculae, perivascular cellular clustering, endothelial wrapping, and centrally located nuclei with granular cytoplasm were helpful features. In selected cases, IPOX studies were critical in arriving at the correct diagnosis.

Biopsy, Fine-Needle↗
PubMed2004

Neonatal behaviors associated with ultrasonic vocalizations in mice (mus musculus): A slow-motion analysis.

Infant rodents emit ultrasonic vocalizations (USVs) when isolated from the mother and littermates. While USVs reportedly promote maternal behavior, their communicatory role is still controversial. We performed a detailed behavioral characterization in 7-day-old CD-1 Swiss mice to describe (a) behavioral patterns accompanying or immediately preceding or following the USV and (b) how selected USV features are modulated according to the behavioral pattern being performed. The present results represent an ethogram of mouse pup behavior in close temporal proximity to USV, providing further information to evaluate the functional role of USVs in the framework of the mother-offspring relationship. A significant increase of head rising behavior immediately prior to the USV and a behavioral activation displayed by pups in conjunction with it suggest that pups behave in a way that may favor interaction with their mothers.

Animal Communication↗
PubMed2007

Breast MRI lesion classification: improved performance of human readers with a backpropagation neural network computer-aided diagnosis (CAD) system.

PURPOSE: To develop and test a computer-aided diagnosis (CAD) system to improve the performance of radiologists in classifying lesions on breast MRI (BMRI). MATERIALS AND METHODS: A CAD system was developed that uses a semiautomated segmentation method. After segmentation, 42 features based on lesion shape, texture, and enhancement kinetics were computed, and the 13 best features were selected and used as inputs to a backpropagation neural network (BNN). The BNN was trained and tested using the leave-one-out method on 80 BMRI lesions (37 benign, 43 malignant). Lesion histopathology was used as the reference standard. Five human readers classified the 80 lesions first without and then with CAD assistance. The performance of the computer classifier and the human readers was assessed using receiver operating characteristic curves; the performance of the human readers was also evaluated using multireader multicase (MRMC) analysis. RESULTS: The performance of the human readers significantly improved when aided by the CAD system (P < 0.05). MRMC analysis showed that human reader performance with and without CAD system assistance can be generalized to the population of cases (P < 0.001). CONCLUSION: A CAD system based on lesion morphology and enhancement kinetics can improve the performance of human readers in classifying lesions on breast MRI.

Breast Neoplasms↗
PubMed2003

Third look surgery and beyond for appendiceal malignancy with peritoneal dissemination.

BACKGROUND AND OBJECTIVES: Second look surgery has been previously studied in patients with recurrent peritoneal dissemination from appendiceal malignancy. However, selection criteria for third, fourth, and subsequent reoperations are not available. METHODS: Five hundred and one patients with epithelial peritoneal surface malignancy of appendiceal origin underwent treatment with cytoreductive surgery and intraperitoneal chemotherapy during an 18-year period. Forty-five of these patients (8.9%) underwent three or more operative interventions. A critical statistical analysis of the impact of selected clinical features on survival was performed from a prospective database. RESULTS: Overall 5-year survival of these 45 patients was 70%. Five- and ten-year survival rates for patients with three interventions were 60 and 48%, for four interventions were 78 and 36%, and for five or more interventions were 100 and 80%. Sites of recurrent disease, histopathologic type of tumor, and lymph node status had no impact on survival. A complete second and third cytoreduction was associated with an improved 5-year survival rate. CONCLUSIONS: Prolonged survival in patients with three or more reoperations was significantly associated with a complete cytoreduction. However, after four or more interventions, the effects of tumor biology may predominate. Although 5-year survival is likely with multiple reoperations, prolonged follow-up shows that cancer cure is a rare event.

Adenocarcinoma, Mucinous↗
PubMed1983

Rhinophyma treated by argon laser.

Results are reported of rhinophyma treated by argon laser. The therapy is assumed to be based on two features: first, selective coagulation of the blood capillaries which cause redness of the nose and which feed the hypertrophic regions; second, direct coagulation shrinkage of the hypertrophic connective tissue. The therapy is simple, causes no noticeable discomfort, requires no (local) anaesthesia or admission, and can be performed more than once. Thirteen patients were treated, eleven men and two women. Systemic treatment could be stopped in all but one case (seven patients). Two out of ten patients still use resorcinol but at a reduced frequency. The general result is a smooth and more natural appearance of the nose without redness. Pustulosis has become an exception.

Adult↗
PubMed1994

Synthetic inhibitors of elastase.

For more than two decades investigators around the world, in both academic and industrial institutions, have been developing inhibitors of human neutrophil elastase. A number of very elegant and insightful strategies have been reported. In the case of reversible peptidic inhibitors, this has resulted in the identification of some extremely potent compounds with dissociation constants in the 10(-11) M range. This is quite an accomplishment considering that these low molecular-weight inhibitors are only tri- and tetrapeptides. In the case of the heterocyclic-based inhibitors, the challenge of balancing the heterocycle's inherent reactivity and aqueous stability with the stability of the enzyme-inhibitor adduct has been meet by either using a latent, reactive functionality which is only activated within the enzyme, or by incorporating features which selectively obstruct deacylation but have little effect on the enzyme acylation step. The underlying goal of this research has been the identification of agents to treat diseases associated with HNE. Several animal models have been developed for evaluating the in vivo activity of elastase inhibitors, and compounds have been shown to be effective in all of these models by the intravenous, intratrachael or oral routes of administration. However, only a very small percentage of compounds have possessed all the necessary properties, including lack of toxicity, for progression into the clinic. The peptidyl TFMK ICI 200,880 (25-12) has many of the desired characteristics of a drug to treat the diseases associated with HNE: chemical stability, in vitro and in vivo activity, a long duration of action, and adequate metabolic stability. Currently ICI 200,880 is the only low molecular-weight HNE inhibitor known to be undergoing clinical trials, and may be the compound which finally demonstrates the clinical utility of a synthetic HNE inhibitor.

Amino Acid Sequence↗
PubMed2006

Liver involvement in neuroblastoma: the Memorial Sloan-Kettering Experience supports treatment reduction in young patients.

BACKGROUND: We reviewed clinical and biologic findings in a series of infants with neuroblastoma (NB) in liver. The aim was to gain insights into improving therapy. PATIENTS AND METHODS: Among 19 newly or recently diagnosed infants with NB in liver, 1987-2002, those with stage 4 involving bone received chemotherapy, while those without bone or extensive bone marrow (BM) involvement were observed or received limited treatment if NB caused life-threatening symptoms. We assessed results in the context of NB treatment risk stratification, which is based on age, stage, and selected biologic features (MYCN, ploidy, histology). RESULTS: Six of eight infants with bone involvement became long-term event-free survivors including 1/2 with MYCN amplification and four who received only 4-6 cycles of chemotherapy; at the end of treatment, four infants had abnormalities in liver +/- the primary site, but these resolved. All 11 infants without bone lesions became long-term survivors with either no cytotoxic therapy or only one cycle of chemotherapy (+/- radiotherapy to liver), including four who had stage 4 and one stage 4S patient who still had NB in BM at age 15 months. CONCLUSIONS: Treatment reduction should be considered for subsets of infants with non-MYCN-amplified widespread NB: stage 4 without bone or extensive BM involvement may not require cytotoxic therapy, stage 4S with symptomatic hepatomegaly may not require multiple cycles of chemotherapy, and classic stage 4 may do well with limited chemotherapy. Persistent liver abnormalities post-treatment may not require continued therapy to achieve a radiologic complete remission.

Bone Marrow Neoplasms↗
PubMed2000

An aphasia database on the internet: a model for computer-assisted analysis in aphasiology.

A web-based software model was developed as an example for data mining in aphasiology. It is used for educating medical and engineering students. It is based upon a database of 254 aphasic patients which contains the diagnosis of the aphasia type, profiles of an aphasia test battery (Aachen Aphasia Test), and some further clinical information. In addition, the cerebral lesion profiles of 147 of these cases were standardized by transferring the coordinates of the lesions to a 3D reference brain based upon the ACPC coordinate system. Two artificial neural networks were used to perform a classification of the aphasia type. First, a coarse classification was achieved by using an assessment of spontaneous speech of the patient which produced correct results in 87% of the test cases. Data analysis tools were used to select four features of the 30 available test features to yield a more accurate diagnosis. This classifier produced correct results in 92% of the test cases. The neural network approach is similar to grouping performed in group studies, while the nearest-neighbor method shows a design more similar to case studies. It finds the neurolinguistic and the lesion data of patients whose AAT profiles are most similar to the user's input. This way lesion profiles can be compared to each other interindividually. The Aphasia Diagnoser is available on the Web address http://fuzzy.iau.dtu.dk/aphasia.nsf and thus should facilitate a discussion about the reliability and possibilities of data-mining techniques in aphasiology.

Aphasia↗