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PubMed1991

Measurement of performance of a peripheral vision lipreading aid.

Lipreading, as the most important tool of speech understanding for profoundly deaf people, carries only a limited amount of information about speech. We explored the usefulness of a peripheral vision display in providing profoundly deaf people with supplementary information to lipreading. A pair of eye-glasses with a commercially available two-dimensional red LED array, and associated electronics was developed. The display is located on the rim of the eyeglasses in the temporal field and the horizontal meridian of the right eye. Selected speech features were encoded as visual patterns for presentation to the lipreader. These features (the fundamental frequency of the speech, high-frequency energy, and low-passed speech signal or total energy envelope) provide information about voicing and plosion/friction in order to supplement lipreading. Experiments with 3 normal and 5 deaf subjects demonstrated the capability of the aid to convey speech information for video taped vowel-consonant-vowel (VCV) nonsense syllables. Average identification of 12 VCV syllables using the aid was about 76%, as compared with 40% without the aid.

Adolescent↗
PubMedDate not supplied

Ultrastructural texture analysis as a diagnostic tool in mouse liver carcinogenesis.

Nuclear texture, which reflects the overall structure of the chromatin, may be used to detect early as well as later stages of malignancy. In this study, texture analysis was applied to four groups of liver cells in mice: normal and regenerating liver, hyperplastic nodules, and hepatocellular carcinomas. The best discriminating set of features was selected based on a training data set. The model was then tested on an independent series of 10 hyperplastic nodules and 6 hepatocellular carcinomas. A correct classification rate of 95% was obtained on the training data set and 100% accuracy was obtained on the test set. This kind of image analysis technique offers an opportunity to identify and describe the nuclear changes related to carcinogenesis, and the present results demonstrate the possible use of digital texture analysis as a diagnostic aid in tumor pathology.

Animals↗
PubMedDate not supplied

Nucleolar organizer regions in congenital mesoblastic nephroma.

A review of 78 renal tumors in patients under 6 months of age revealed 35 congenital mesoblastic nephromas (CMNs). Based on cellular criteria, 14 were classified as classical, 4 as partly cellular, and 17 as cellular CMN. The mean ages were 24, 11, and 70 days, respectively. There were 13 intrarenal tumors (stage I) but 9 classical, 3 partly cellular, and 5 cellular CMNs extended to the perirenal fat (stage II) and 5 cellular tumors ruptured (stage III). In order to assess cellular proliferative activity, silver staining of nucleolar organizer region (Ag-NOR) proteins was performed on 19 CMNs. The number of Ag-NOR dots per cell was significantly lower in classical and partly cellular CMN than in cellular CMN, whatever the stage (P < .01). Within the cellular CMNs, the mean number of Ag-NOR dots was statistically higher in the single case that recurred with fatal outcome (P < .02). Counting of Ag-NOR dots appears to be a reproducible method for evaluating the biologic potential of CMNs. The number of Ag-NOR dots, DNA content measurements, the histological subclassification, and the presence or absence of tumor at the surgical margins may be useful features in selecting those patients who will benefit from further treatment after nephrectomy.

Female↗
PubMed2005

Evaluating a food bank recipe-tasting program.

Food banks mitigate immediate food insecurity, but their ability to promote healthy nutrition is constrained by how often recipients may visit and the range of foods available. In a descriptive study, a formative evaluation was completed of a combined heart-healthy recipe-tasting and education program that aims to promote healthy eating knowledge and skills in a group of food bank recipients in Hamilton, Ontario. Fifty-five adults were surveyed about food bank attendance, program awareness, perceived enhancement of knowledge and skills, and suggestions for program improvement. Most participants (73%) were positive about the program, and 91% wanted the program to continue. In addition, 78% would prepare the recipes sampled. In contrast, program awareness and planning food bank visits to coincide with the program were generally low. Food banks are potential sites for effective nutrition promotion programs. To reach more recipients, more frequent implementation and seeking the use of a designated room are suggested for the current program. The findings also suggest that the sampling approach to promoting healthy eating to food bank recipients deserves further study. For example, monitoring the selection of featured recipe ingredients would be a useful indicator of behaviour.

Adult↗
PubMed2005

Evaluation of serum cathepsin B and D in relation to clinicopathological staging of colorectal cancer.

AIM: Proteolytic degradation of the extracellular matrix facilitates cancer invasion and promotes metastasis. The study aims at evaluation of preoperative and postoperative serum cathepsins B and D levels in correlation with selected anatomoclinical features of colorectal cancer. METHODS: Blood samples were collected from 63 colorectal cancer patients before curative operation of the tumor 10 d later. Blood that was obtained from 20 healthy volunteers, served as a control. The activity of cathepsin B was measured with Bz-DL-arginine-pNA as a substrate at pH 6.0, while cathepsin D activity was determined with urea-denatured hemoglobin (pH 4.0). RESULTS: The preoperative and postoperative activities of cathepsin B were significantly (P<0.00001) lower in serum of colorectal cancer patients than in control group. However, postoperative values of this protease were significantly increased in comparison with preoperative ones (P = 0.031). Activity of cathepsin D appeared to be significantly higher in colorectal cancer sera (P<0.00001) compared with controls. No statistically significant differences between preoperative and postoperative activity of cathepsin D were noted (P = 0.09). We revealed a strong linkage of cathepsins' levels with lymph node status and pT stage of colorectal cancer. CONCLUSION: Blood serum activities of cathepsin B and D depend on the time of sampling, tumor size and lymph node involvement. Significantly, increased activity of cathepsin D could indicate a malignant condition of the large intestine. In our work, the serum postoperative decrease of cathepsin B activity appears as an obvious concomitant of local lymph node metastasis-the well-known clinicopathological feature of poor prognosis.

Aged↗
PubMed1998

Response times and eye movements in feature and conjunction search as a function of target eccentricity.

In four experiments, saccadic eye movements, reaction times (RTs), and accuracy were measured as observers searched for feature or conjunction targets presented at several eccentricities. A conjunction search deficit, evidenced by a large eccentricity effect on RTs, accuracy, and number of saccades, was seen in Experiments 1A and 1B. Experiment 2 indicated that, when saccades were precluded, there was an even larger eccentricity effect for conjunction search targets. In Experiment 3, practice in a conjunction search task allowed both RT and number of saccades to become independent of eccentricity. Additionally, there was evidence of feature-based selectivity in that observers were more likely to fixate distractors that had the same contrast as the target. Results are consistent with the view that the oculomotor and attentional systems are functionally linked and provide constraints for models of visual attention and search.

Attention↗
PubMed2002

Completing the corticofugal loop: a visual role for the corticogeniculate type 1 metabotropic glutamate receptor.

The way in which the brain deals with sensory information relies not only on feedforward processing of signals from the periphery but also on feedback inputs. This is the case of the massive projection back from layer 6 in the visual cortex to the thalamus, for which, despite being the greatest single source of synaptic contacts, the functional role still remains unclear. In the cat lateral geniculate nucleus, part of this cortical feedback is mediated by type 1 metabotropic glutamate receptors (mGluR1s), which are exclusively located on distal segments of the relay-cell dendrites. Here we show that in adult cats the cortex uses a synaptic drive mediated by these receptors (mGluR1) specifically to enhance the excitatory center of the thalamic receptive field. Moreover the effect is maximum in response to those stimuli that effectively drive cortical cells, and importantly, it does not affect the spatiotemporal structure of the thalamic receptive field. Therefore, cortex, by closing this corticofugal "loop," is able to increase the gain of its thalamic input within a focal spatial window, selecting key features of the incoming signal.

Action Potentials↗
PubMed1997

Decision support and data analysis tools for risk assessment in primary preventive study of atherosclerosis.

In the paper we show results of two programs applied for data analysis and decision support in primary preventive study of atherosclerosis. First program E.T. (Epidemiology Tools) can be used for analysis of data from retrospective (case-control) studies, prospective (cohort) studies and for standardization. Second program called CORE (COnstitution and REduction) supports the process of selection of features that are relevant for given decision making task. Program CORE is using information theory approach. Both these programs were applied to analysis of data about 1417 middle age men collected in the longitudinal study on atherosclerosis in urban population. Apart from these two new programs we have analyzed data also by the STATISTICA software.

Adult↗
PubMed1998

Oleamide: an endogenous sleep-inducing lipid and prototypical member of a new class of biological signaling molecules.

Oleamide is an endogenous fatty acid primary amide that accumulates in the cerebrospinal fluid under conditions of sleep deprivation and induces physiological sleep in animals. A review covering its discovery, its implications, and the emerging biology surrounding its discovery is presented. Consistent with its role as a prototypical member of a new class of biological signaling molecules, enzymatic regulation of endogenous concentrations of oleamide have been characterized or proposed. Fatty acid amide hydrolase (FAAH) is an integral membrane protein that degrades oleamide and potent inhibitors with physiological sleep-inducing properties have been disclosed. The characterization, cloning, and neuronal distribution of FAAH have been detailed and the enzyme was found to possess the ability to hydrolyze a range of fatty acid amides including anandamide which serves as the endogenous ligand for the cannabinoid receptor. An additional endogenous substance with REM sleep-inducing properties, 2-octyl gamma-bromoacetoacetate, was characterized as a potent FAAH inhibitor. Oleamide has been shown to modulate serotonergic neurotransmission and inhibit intercellular gap junction communication and detailed studies of its well defined and selective structural features required for activity have been disclosed.

Animals↗
PubMed1976

[Ultrastructural aspects of the migration of somite cells to the posterior limb buds of mice].

Migrating cells originating selectively in the ventral lateral edge of the somites adjacent to the mouse hindlimb bud have been studied in transverse sections by transmission and scanning electron microscopy. Collected during the 10th and 11th gestational days, the embryos have been classified according to the number of metameres. As soon as the 28 somite stage, discrete cytological modifications occur in a limited caudal area of the ventro-lateral somitic edge. Loosing the typical epithelial arrangement characteristic of the dermatome cells, these ventral cells show large areas of close contact between their plasma membrane and a superficial microfilamentous material accumulates in the contact areas. At the 33 somite stage, the same groups of cells elongate and form long cellular trails invading the proximal area of the limb bud mesoderm. The migrating cells become polarized along the migrating axis and they retain large and smooth intercellular contacts with each other. Very selective ultrastructural features of the migrating somitic cells can be interpreted in relation to their cinetic activity or to their early myogenic differentiation. In addition to their mutual superficial relationships, the migrating cells are characterized by the presence of numerous oriented microtubules, of a high number of active mitochondria, of an abundant granular endoplasmic reticulum and of an hypertrophied Golgi apparatus regularly located near the nucleus in the "trailing" edge of the cells. Several dense granules with a diameter of 8 nm are present in the mitochondrial matrix. The extensive Golgi apparatus is associated to numerous thick walled vesicles, which increase from 60 to 150 nm in diameter as they become closer and closer to the plasma membrane. These vesicles are absent in the mesodermal cells of somatopleural origin; their presence in the migrating somitic cells is probably related to an early myogenic differentiation. The observation made near the distal end of the somitic cellular trails suggests that the more distal somitic cells rapidly loose their ultrastructural particularities as soon as they are dispersed in the limb bud mesoderm; this aspect of the processus, however, requires the study of later developmental stages. Other observations made in the same material bring some precisions to the ecto-mesodermal relationships which are established in the apical area of the limb bud. Scanning electron microscopic observations of thick sections reveal that the outer mesodermal cells of this area send numerous filopodia which make contact with the basement membrane underlying the apical ectodermal ridge.

Animals↗
PubMed1999

Self-assessment of the forensic value of dental records.

One of the most important aspects of a person's dental record may well prove to be it's potential value should the forensic dental identification of their remains become necessary. The better the quality of the antemortem dental records, the easier and faster the identification of the remains will be. The forensic dentist must be able to select identifying features by decoding the deceased's antemortem dental records. A study was conducted on two groups of dentists who were asked to self-assess the forensic dental value of the dental records maintained in their own practices. The three most frequently recorded identifying dental features, other than caries and restorations, were the presence of diastemas, displaced or rotated teeth, and dental anomalies. Surveyed dentists imbedded identifying information into the removable prosthetic devices fabricated for their patients an average of only 64% of the time. Only 56% of the two groups combined felt that their dental chartings and written records would be extremely useful in dental identifications. It is concluded that the quality of antemortem dental records available for comparison to postmortem remains varies from inadequate to extremely useful. Practicing dentists can become valuable members of the dental identification process by developing and maintaining standards of record keeping which would be valuable in restoring their patients' identity.

Adult↗
PubMed1999

Animal models for motor neuron disease.

Motor neuron disease is a general term applied to a broad class of neurodegenerative diseases that are characterized by fatally progressive muscular weakness, atrophy, and paralysis attributable to loss of motor neurons. At present, there is no cure for most motor neuron diseases, including amyotrophic lateral sclerosis (ALS), the most common human motor neuron disease--the cause of which remains largely unknown. Animal models of motor neuron disease (MND) have significantly contributed to the remarkable recent progress in understanding the cause, genetic factors, and pathologic mechanisms proposed for this class of human neurodegenerative disorders. Largely driven by ALS research, animal models of MND have proven their usefulness in elucidating potential causes and specific pathogenic mechanisms, and have helped to advance promising new treatments from "benchside to bedside." This review summarizes important features of selected established animal models of MND: genetically engineered mice and inherited or spontaneously occurring MND in the murine, canine, and equine species.

Amyotrophic Lateral Sclerosis↗
PubMed1999

Experimental lesion of medial frontal cortex mediates inhibition of expression of carbohydrate-binding sites in the spleen macrophages in rat.

The fundamental concept of a neuroimmunological network is well appreciated although detailed description of the individual mechanisms has not yet been attained. In an effort to close this gap, the effect of electrolesion of the frontal medial cortex, a structure with the known "immunoreactivity", on selected phenotypic features of spleen macrophages was studied. Since sugar receptors (lectins) are pivotal for recognition, custom-made tools termed neoglycoproteins were employed to delineate any injury-induced changes of their expression. The total number of macrophages in the spleen red pulp was assessed using the ED-1 monoclonal antibody. The results showed that after lesion of the medial frontal cortex, the extent of expression of carbohydrate-binding sites in red pulp spleen macrophages significantly decreased without affecting the total number of these cells. These data intimate that distinct brain regions are involved in the control of the phenotype of macrophages in the central lymphoid organs by currently elusive biochemical mechanisms.

Animals↗
PubMed1975

Epidemiology and aetiology of cancer of the uterine cervix including the detection of carcinogenic N-nitrosamines in the human vaginal vault.

Cancer of the uterine cervix occurs with high frequency in black females of several populations of Southern Africa. It accounts for 40-50% of all cancers in Black females in the Johannesburg area and for over 40% of those in women in the rural lowveld area of the Transvaal. The aetiology of this cancer has several distinct features, almost all of which concern some or other aspect of coitus. Age at first coitus and at first marriage, and promiscuity, are very strongly associated with the development of the disease, and age, race, religion, culture, socio-economic status, extent of genital hygiene and venereal disease also play a major role. In spite of current belief, circumcision of the male partner is at best weakly associated with the development of the disease, and so are menstruation, coital habits and pregnancy. Certain aetiological features are selectively discussed; these include Herpesvirus type II, 'rogue' spermatozoa and the recent isolation of a group of potent carcinogens, the nitrosamines, in infected discharge samples taken from the vaginal vault of patients attending gynaecological clinics.

Black or African American↗
PubMed2000

Quantitative grading of rat esophageal carcinogenesis using computer-assisted image tile analysis.

Our objective was to grade, by computer-assisted quantitative image tile analysis, the intraepithelial neoplasia (also called dysplasia) that develops in esophagi of rats given N-nitrosomethybenzylamine (NMBA) for 5 weeks. To perform image tile analysis, the computer divides the video image of the neoplastic epithelium into a row of contiguous small rectangular images, or "tiles," 84 x 292 microm in size, and quantitatively measures four selected tissue features within each image tile. The computer then calculates a tile grade for each image tile as the weighted sum of the four feature measurements, transformed into statistical Z-scores, the weights being determined by Fisher linear discriminant analysis of 300 tile grades of the neoplastic epithelium referenced to the mean tile grade (MTG) of 300 image tiles of normal epithelium. The two grading parameters, MTG and the percentage of tile grades exceeding the MTG of normal epithelium by >4 SD units (%TG>4SD), were validated as endpoints for screening chemopreventive agents in the rat NMBA-induced esophageal carcinogenesis model in two ways: (a) after NMBA treatment, %TG>4SD developed in parallel with tumor incidence and tumor multiplicity (number of papillomas/tumor-bearing rat); and (b) placing the chemopreventive phenethylisothiocyanate in the food of NMBA-treated rats produced parallel reductions in MTG, tumor incidence, and tumor multiplicity. Both MTG and %TG>4SD, measured by quantitative image tile analysis, are sensitive and objective continuous parametric response variables expressed to three significant figures, with wide dynamic range, that may be evaluated by t tests to compare tissue neoplastic changes before and after treatment with a chemopreventive agent.

Administration, Oral↗
PubMed1999

Epidemiologic pattern of esophageal cancer at an inner-city university hospital.

The incidence of esophageal adenocarcinoma has increased significantly during the past 25 years in the United States and Europe. This increase has occurred predominantly among white men. To determine the effect of ethnicity and selected clinical features on the type of esophageal cancer in an urban, minority population, we retrospectively reviewed esophageal cancer at our institution. All patients with esophageal cancer from 1980 to 1995 were identified using the tumor registry data base and patient medical records at UMDNJ-University Hospital. Inclusion criteria were self-reported ethnicity and a confirmed pathologic diagnosis of either esophageal adenocarcinoma (ADENO) or squamous cell carcinoma (SCCA). Data abstracted from the record included age and year of diagnosis, weeks of survival, and risk factors, such as Barrett's esophagus and tobacco and alcohol abuse. Of 150 cases of esophageal cancer, 139 (93%) were SCCA and 11 (7%) were ADENO; the male:female ratio was 11:4. African and Latino Americans comprised 87% and white Americans 13% of the group. The incidence of ADENO increased during the study period: 1980-1984, 1 case; 1985-1989, 3 cases; and 1990-1995, 7 cases (P = .022); whereas the incidence of SCCA remained constant during the same intervals: 51, 52, and 36 cases, respectively (P > .05). By ethnicity, ADENO occurred more frequently among whites (7/19, 37%) than among African and Latino Americans (4/131, 3%); SCCA was more common among African and Latino Americans (127/131, 97%) than among whites (12/19, 63%) (P < .001). Other risk factors did not influence the type of esophageal cancer. The study concluded that the incidence of ADENO increased, primarily among white men, from 1980 to 1995 at UMDNJ-University Hospital. In contrast, the incidence of SCCA remained constant and was the primary type of esophageal cancer in African and Latino Americans. This study supports previous reports that ethnicity influences the histology of esophageal cancer.

Adenocarcinoma↗
PubMed1998

Domenico Battini and his description of congenital megacolon: a detailed case report one century before Hirschsprung.

More than one century after the epochal paper of Harald Hirschsprung, and in spite of fast and remarkable advances in the pathophysiology of congenital megacolon, our understanding of how bowels may become functionally obstructed, and especially its variability, remains largely incomplete. While much more needs to be known about normal gastrointestinal physiology, an interaction between genetic and environmental factors seems to be of paramount importance in the pathogenesis of Hirschsprung's disease. While reviewing the relevant literature, we came across a virtually unknown contribution by an Italian physician, Domenico Battini, who happened to follow-up for about 10 years a case of severe constipation. This contribution, published posthumously as a book in 1800, not only describes very carefully the clinical evolution of that patient, but also provides a detailed post-mortem examination of the abdominal viscera, with particular reference to the alterations occurred in the intestines. We conclude that Battini, nearly one century before Hirschsprung, had succeeded in reporting a typical case of congenital megacolon, and had perceived a number of features (familiarity, selective involvement of "neural layers" in the gut mucosa) that were to become characteristic of Hirschsprung's disease a few decades after Hirschsprung himself had published his article.

Hirschsprung Disease↗