Showing papers by "Nova Southeastern University published in 2005"

Bisphosphonate-associated osteonecrosis of mandibular and maxillary bone: an emerging oral complication of supportive cancer therapy.

Abstract: BACKGROUND The current report presented 17 patients with cancer with bone metastases and 1 patient with osteopenia who received treatment with bisphosphonates and who subsequently developed osteonecrosis of the mandible and/or maxilla. METHODS The authors reviewed information on 18 patients who were referred to oral medicine or oral surgery specialists for evaluation and treatment of mandibular and/or maxillary bone necrosis from June 2002 to September 2004. To be included in the current review, patients must have been treated with either pamidronate or zoledronic acid to control or prevent metastatic disease, or with alendronate for osteoporosis. All patients with cancer had received chemotherapy while receiving bisphosphonate management. RESULTS The 17 patients with cancer were receiving active medical care for a malignancy. Cancer treatment included a variety of chemotherapeutic agents. They presented with metastatic disease to bone and were treated intravenously with the bisphosphonates pamidronate or zoledronic acid for a mean time of 25 months (range, 4–41 mos). There were 14 females and 4 males with a mean age of 62 years (range, 37–74 yrs). Malignancies included breast carcinoma (n = 10), multiple myeloma (n = 3), prostate carcinoma (n = 1), ovarian carcinoma (n = 1), prostate carcinoma/lymphoma (n = 1), and breast/ovarian carcinoma (n = 1). One female patient with osteopenia received alendronate. The most common clinical osteonecrosis presentations included infection and necrotic bone in the mandible. Associated events included dental extractions, infection, and trauma. Two patients appeared to develop disease spontaneously, without any clinical or radiographic evidence of local pathology. Despite surgical intervention, antibiotic therapy, hyperbaric oxygen therapy, and topical use of chemotherapeutic mouth rinses, most of the lesions did not respond well to therapy. Discontinuation of bisphosphonate therapy did not assure healing. However, 1 patient with cancer healed after discontinuation of bisphosphonate therapy for 4 months. CONCLUSIONS The findings in the patient population combined with recent literature reports suggested that bisphosphonates may contribute to the pathogenesis of the oral lesions. The risk factors and precise mechanism involved in the formation of the osteonecrosis are not known. This condition represents a new oral complication in patients with cancer and can be termed bisphosphonate-associated osteonecrosis. Lesions in patients with osteoporosis are worrisome and need to be further evaluated. Cancer 2005. © 2005 American Cancer Society.

Managing the care of patients with bisphosphonate-associated osteonecrosis: an American Academy of Oral Medicine position paper.

Abstract: Background This position paper addresses the prevention of bisphosphonate-associated osteonecrosis (BON) and the management of care of patients with cancer and/or osteoporosis who are receiving bisphosphonates and who have BON or are at risk of developing it. Methods The authors reviewed the literature available on this newly described oral complication. Information of interest included bisphosphonates, the medications associated with this oral complication; the patient population at risk of developing BON and the diseases being treated with this class of medications; the clinical presentation of the oral lesions; guidelines for managing the care of patients who develop BON; the prevention of this complication based on current knowledge; and recommendations for routine dental treatment of patients receiving bisphosphonates. Results There is strong evidence that bisphosphonate therapy is the common link in patients with BON. The pathobiological mechanism leading to BON may have to do with the inhibition of bone remodeling and decreased intraosseous blood flow caused by bisphosphonates. People at risk include patients with multiple myeloma and patients with cancer metastatic to bone who are receiving intravenous bisphosphonates, as well as patients taking bisphosphonates for osteoporosis. The risk of developing complications appears to increase with time of use of the medication. There are no guidelines based on evidence, and the clinical management of the oral complication is based on expert opinion. Conclusion Prevention of BON is the best approach to management of this complication. Existing protocols to manage the care of patients who will receive radiation therapy or chemotherapy may be used until specific guidelines for BON are developed.

Resource-Based View of Knowledge Management for Competitive Advantage

Abstract: We are not only in a new millennium, but also in a new era: the knowledge era Sustainable competitive advantage is dependent on building and exploiting core competencies The resource-based view (RBV) of the firm defines a strategic asset as one that is rare, valuable, imperfectly imitable and non-substitutable Knowledge is seen as a strategic asset with the potential to be a source of competitive advantage for an organization In this paper, we provide a model that examines how and why knowledge management (KM) can be used to create competitive advantage from the RBV of the

Impact of Gender Role Conflict, Traditional Masculinity Ideology, Alexithymia, and Age on Men's Attitudes Toward Psychological Help Seeking.

Abstract: Adult male volunteers (N = 155) completed the Gender Role Conflict Scale-I, Male Role Norms Inventory—Revised, Bermond-Vorst Alexithymia Questionnaire, and Attitudes Toward Seeking Professional Psychological Help Scale. Data were analyzed using regression analysis. Results indicate that men who scor

Using data mining as a strategy for assessing asynchronous discussion forums

Abstract: The purpose of this paper is to show how data mining may offer promise as a strategy for discovering and building alternative representations for the data underlying asynchronous discussion forums. Presently, the instructor's view of the output of a threaded forum is limited to reviewing a transcript or print version of the written dialogue produced by participants. With potentially hundreds of contributions to review for an entire online course, the instructor lacks a comprehensive view of the information embedded in the transcript. In this context, the authors attempt to sort out the question, "what is data from an online forum?" among other key questions. The present work seeks to intersect the information (i.e., participation indicators) an instructor may wish to extract from the forum with viewable and useful information that the system could produce from the instructor's query. Temporal participation indicators are used to show how using data and text mining techniques in the query process could improve the instructor's ability to evaluate the progress of a threaded discussion.

Minimum spanning tree partitioning algorithm for microaggregation

Abstract: This paper presents a clustering algorithm for partitioning a minimum spanning tree with a constraint on minimum group size. The problem is motivated by microaggregation, a disclosure limitation technique in which similar records are aggregated into groups containing a minimum of k records. Heuristic clustering methods are needed since the minimum information loss microaggregation problem is NP-hard. Our MST partitioning algorithm for microaggregation is sufficiently efficient to be practical for large data sets and yields results that are comparable to the best available heuristic methods for microaggregation. For data that contain pronounced clustering effects, our method results in significantly lower information loss. Our algorithm is general enough to accommodate different measures of information loss and can be used for other clustering applications that have a constraint on minimum group size.

Sensory modulation and affective disorders in children and adolescents with Asperger's disorder.

Abstract: OBJECTIVE. The purpose of the study was to determine if there were significant relationships between dysfunction in sensory modulation, symptoms of affective disorders, and adaptive behaviors in children and adolescents with Asperger’s disorder between 6 and 17 years of age. METHOD. Parents of 50 children and adolescents between 6 and 17 years of age diagnosed with Asperger’s disorder based on the Diagnostic and Statistical Manual of Mental Disorders-IV criteria completed the (a) Sensory Profile for children 6 to 10 years of age or the Adolescent/Adult Sensory Profile for adolescents 11 to 17 years of age; (b) the Adaptive Behavior Assessment System: Parent Version; (c) Revised Children’s Manifest Anxiety Scale Adapted Parent’s Version; and (d) the Children’s Depression Inventory Adapted Parent’s Version. Descriptive statistics and the Pearson product-moment coefficient of correlation calculations were used for data analysis. RESULTS. The results indicated that there were significantly strong positive correlations between sensory defensiveness and anxiety (r = .476, p = .000) in children and adolescents with Asperger’s disorder. There were also significant relationships between symptoms of depression and hyposensitivity in the total group (r = .214, p = .05) and the older group (r = .492, p = .027). There were no significant relationships between depression and overall adaptive behavior (r = ‐.243, p = .089) or anxiety and overall adaptive behavior (r = ‐.108, p = .455). Significantly strong inverse relationships were found between the specific adaptive behaviors of functional academics, leisure, social skills, and symptoms of depression. Functional academics were also significantly inversely related to anxiety. Specifically, sensory hyper- and hypersensitivity were significantly inversely related to community use and social skills. CONCLUSION. The data supports positive relationships between anxiety and sensory defensiveness in all age ranges and a relationship between depression and hyposensitivity in older children. Stronger inverse relationships were apparent between specific adaptive behaviors including: (a) symptoms of depression and functional academics, leisure, social skills; (b) anxiety and functional academics; and (c) both sensory hyper- and hyposensitivity and community use and social skills. In this study, as the symptoms of affective disorders increased in children and adolescents with Asperger’s disorder, the functional performance in the adaptive behaviors of functional academics and social skills appeared to decrease. Performance in the adaptive behaviors of community use and socials skills appeared to decrease as symptoms of dysfunction in sensory modulation increase. Further research is necessary to determine the impact of treatment for dysfunction on sensory modulation on affective disorders and performance in specific adaptive behaviors.

What Can You Learn from a Cell Phone? Almost Anything!.

Abstract: One and a half billion people, all over the world, are walking around with powerful computers in their pockets and purses The fact is they often do not realize it, because they call them something else But today 's high-end cell phones have the computing power of a mid-1990s personal computer (PC)—while consuming only one one-hundredth of the energy Even the simplest, voice -only phones have more complex and powerful chips than the 1969 on-board computer that landed a spaceship on the moon

What Would a State of the Art Instructional Video Game Look like

Abstract: What would a state of the art instructional video game look like? As far as I am concerned, we already know the answer to this question. A good many of the best commercial video games are already state of the art learning games—though their designers would go broke if too many people knew this, thanks to the poor reputation our schools have given learning in recent years (Coles 2003). A good instructional game, like many good commercial games, should be built around what I call "authentic professionalism." In such games, skills, knowledge, and values are distributed between the virtual characters and the real-world player in a way that allows the player to experience first-hand how members of that profession think, behave, and solve problems.

Marine reserve design and evaluation using automated acoustic telemetry: A case-study involving coral reef-associated sharks in the mesoamerican Caribbean

Abstract: A non-overlapping acoustic receiver array was used to track the movements of two common shark species, nurse Ginglymostoma cirratum (n=25) and Caribbean reef Carcharhinus perezi (n=5), in and around Glover’s Reef Marine Reserve (GRMR), off the coast of Belize, between May and October, 2004. Although both species exhibited partial site fidelity in that they were most likely to be detected near the area of original capture, both species also moved widely throughout the 10 by 30 km atoll. One Caribbean reef shark was detected by a monitor at Lighthouse Reef, 30 km from Glover’s Reef across deep (>400m) open water. The mean minimum linear dispersal (MLD) was 10.5 km for Caribbean reef sharks and 7.7 km for nurse sharks, with many individuals traveling more than the 10 km width of the no-take “conservation zone” of the marine reserve. Although most sharks were tagged within the conservation zone, individuals were detected outside this part of GRMR on average 48 days out of the 150 days of observations. However, of 7 nurse sharks tagged near the center of the conservation zone, 4 were never detected outside of this part of the reserve. In general, this study suggests that effective conservation of these large roving predators requires an ecosystem-based management approach including a zoned management plan, similar to that used at GRMR, in which a fairly large no-take reserve, incorporating diverse habitats and the connections between them, is surrounded by a larger area in which fishing is regulated. S I N T R O D U C T I O N harks are increasingly threatened by overexploitation and habitat degradation around the world, and marine reserves are now being considered as a potential component of conservation strategies for these top-predators (Camhi, 1998; FAO, 2000; Watts, 2001; Baum et al., 2003; Simpfendorfer & Heupel, 2004). However, because sharks can range widely (Kohler et al., 1998; Holland et al., 1999; Boustany et al., 2002) and no-take marine reserves will

Global-scale genetic identification of hammerhead sharks: Application to assessment of the international fin trade and law enforcement

Abstract: The future status of sharks is an issue of widespread conservation concern due to declines in many species in the face of high levels of exploitation to satisfy market demands for products, especially fins. Substantial declines in the large-bodied hammerhead sharks, Sphyrna lewini, S. mokarran and S. zygaena, even in regions where some management occurs, indicate that informed conservation measures are warranted for these circumglobally distributed species. Despite the importance of assessing shark catch and trade on a species-specific basis to detect potential overexploitation of individual species, achieving this goal for hammerheads has proven elusive due to difficulties in identification of their products. Here, we present the development and application of a diagnostic, streamlined, five-primer multiplex polymerase chain reaction assay utilizing species-specific primers based on nuclear ribosomal ITS2 for the three hammerhead species throughout their global distribution. Application of this assay to investigations of the fin market confirmed the presence of hammerhead fins in the international trade. A study of the world’s largest fin market in Hong Kong revealed a high concordance between specific Chinese-name trade categories and fins from these three species (‘‘Bai Chun’’ with S. lewini, ‘‘Gui Chun’’ with S. zygaena and ‘‘Gu Pian’’ with S. mokarran), and clear species preferences. This concordance information allows the use of market records for monitoring species-specific trends in trade and exploitation rates. The assay is also proving useful for identification of shark body parts in U.S. fisheries law-enforcement activities. Screening of morphologically identified ‘‘ S. lewini’’ from globally distributed areas using this assay with subsequent whole ITS2 sequencing suggests a cryptic species closely related to S. lewini occurs off the SE USA coast.

Conversion of one-step to two-step self-etch adhesives for improved efficacy and extended application.

Abstract: Purpose One-step self-etch adhesives have restricted use due to their acid-base incompatibility with autocured composites and their behavior as permeable membranes after polymerization. This study examined the feasibility of their conversion to two-step self-etch adhesives via the adjunctive use of a non-solvented, relatively hydrophobic resin coating. Methods iBond, Xeno III and Adper Prompt were used either in multiple coats, or in a single coat followed by the use of a layer of Scotchbond Multi-Purpose Plus bond resin for coupling to light- and auto-cured composites. Four types of experiments were performed. Bonded specimens were examined with TEM after immersion in an ammoniacal silver nitrate tracer. Fluid flow measurements of iBond were conducted using the two application protocols to compare the permeability of the bonded dentin with the original smear layer. Permeability of vital dentin bonded with both application protocols were compared for the transudation of dentin fluid across the bonded dentin. Microtensile bond strengths of dentin bonded with the two protocols were examined for their compatibility with an auto-cured composite. Results The results of the four experiments were complementary. iBond and Xeno III exhibited "apparent incompatibility" to auto-cured composites that resulted from their inherent permeability. This was confirmed by the presence of dentin fluid transudate on the adhesive surfaces when they were bonded to vital dentin. Conversely, Adper Prompt exhibited "true incompatibility" to auto-cured composites that was caused by adverse acid-base interaction, masking the inherent permeability of this adhesive. "True" and "apparent" incompatibility issues were eliminated upon their conversion to two-step self-etch adhesives.

Longevity of occlusally-stressed restorations in posterior primary teeth.

Abstract: PURPOSE To compile a survey of the longevity and reasons for failure of stainless steel crowns, amalgam, glass-ionomer, composite and compomer restorations in stress-bearing cavities of primary molars. METHODS This work reviewed the dental literature of 1971 up to July 2003 for longitudinal, controlled clinical studies and retrospective cross-sectional studies. Only studies investigating the clinical performance of restorations in primary teeth with an observation period of at least 2 years were included. Annual failure rates of stainless steel crowns, amalgam, glass-ionomer, composite and compomer restorations were determined and failure reasons were discussed. RESULTS Annual failure rates in stress-bearing cavities of primary molars were determined to be: 0-14% for stainless steel crowns, 0-35.3% for amalgam restorations, 0-25.8% for glass-ionomer restorations, 2-29.1% for atraumatic restorative treatments, 0-15% for composite restorations, and 0-11 for compomer restorations. Main reasons for failure were secondary caries, marginal deficiencies, fracture, and wear.

Visual Field Defects and the Risk of Motor Vehicle Collisions among Patients with Glaucoma

Abstract: RESULTS. With respect to the better-eye AGIS score, compared with patients with no visual field defect, those with severe defects (scores 12‐20) had an increased risk of an MVC (odds ratio [OR] 3.2, 95% CI 0.9‐10.4), although the association was not statistically significant. Moderate (6‐11) or minor field defects (1‐5) in the better eye were not associated with the risk of involvement in a crash. In the worse eye, patients with moderate or severe field defects were at significantly increased risk of an MVC (OR 3.6, 95% CI 1.4‐9.4 and OR 4.4, 95% CI 1.6‐12.4, respectively) compared with those with no defects. Minor field defects in the worse eye did not increase risk of MVC (OR 1.3, 95% CI 0.5‐3.4). CONCLUSIONS. Patients with glaucoma who have moderate or severe visual field impairment in the central 24° radius field in the worse-functioning eye are at increased risk of involvement in a vehicle crash. (Invest Ophthalmol Vis Sci. 2005;46: 4437‐4441) DOI:10.1167/iovs.05-0750

Spatial and temporal dynamics of Arabian Gulf coral assemblages quantified from remote-sensing and in situ monitoring data

Abstract: We analysed spatial patterns of coral communities mapped from IKONOS satellite imagery in combination with 8 yr of traditional ecological monitoring data and archived sea-surface temperature data to explain why coral assemblages in the SE Arabian Gulf (Jebel Ali, Dubai) are impoverished and most do not build reefal frameworks. Analysis of archive sea-surface temperature (SST) data confirmed that the area is subject to recurrent and cyclic temperature anomalies at a frequency which suggests at least a partial link to the El Nino Southern Oscillation via the Indian Ocean Zonal Mode. Classification of high-resolution (4 m pixel-size) IKONOS satellite data gave a large-scale synoptic overview of substrate zonation which, in tandem with a long-term ecological time-series study, allowed us to determine the spatial and temporal dynamics of the coral community. We show that the spatial expression of 4 coral assemblages, as mapped using the IKONOS imagery, is consistent with what would be predicted if reef development was repeatedly 'reset' on a decadal time-scale following recurring episodes of coral mass mortality induced by severe SST anomalies. Furthermore, merging the remotely sensed map of substrate distribution with a detailed bathymetric digital elevation model, revealed no evidence of any significant framework development in the past, suggesting that the cycle of temperature-induced mortality has been operating for some considerable time.

Biological factors in dental caries enamel structure and the caries process in the dynamic process of demineralization and remineralization (part 2).

Abstract: Dental caries is a complex disease process that afflicts a large proportion of the world's population, regardless of gender, age and ethnicity, although it does tend to affect more indivduals with a low socioeconomic status to a greater extent. The physicochemical properties of the mineral comprising the tooth surface and subsurface modulate the development, arrestment and remineralization of dental caries. Post-eruption maturation of enamel surfaces and exposed root surfaces is important in order for more susceptible mineral phases to be modified by incorporation of soluble fluoride from the plaque into dental hydroxyapatite. The chemical reactions that occur during acidic conditions when tooth mineral dissolves (critical pH) are determined by the supersaturation of calcium and phosphate within plaque and saliva, as well as if fluoride is present.

What Can K-12 School Leaders Learn from Video Games and Gaming?.

Abstract: Schools have much to learn from video games and the gaming community. By providing compelling activities for motivating otherwise indifferent learners, video games can potentially help teachers improve the design of learning environments. However, there are considerable rhetorical and practical barriers between the schooling and gaming communities grounded in fundamentally different approaches to learning. Whereas schools are moving toward increasingly standardized learning experiences, games offer the prospect of user-defined worlds in which players try out (and get feedback on) their own assumptions, strategies, and identities. It is difficult, at first glance, to see how gaming can help teachers meet the demands of an increasingly standards-driven public schooling system.

A "Reef-Up" approach to classifying coral habitats from IKONOS imagery

Abstract: Monitoring coral reef benthos with satellites has typically followed a "sensor-down" approach, with the classification algorithm driven by statistics derived from the imagery. I adopt a "reef-up" method, drawing on statistics derived from hyperspectral optical field measurements of substrate reflectance to train image classification. In order to calibrate the satellite data with direct physical measurements of reflectivity, it is necessary to process both the imagery and in situ data to common units of albedo. Building upon a proof-of-concept study conducted by the author in the Red Sea, the link is made by correcting the remote sensing data for the effect of varying bathymetry using in situ measurement of water column optical properties and a digital elevation model constructed from a vessel-based acoustic survey, thereby yielding units of substrate reflectance. Extensive ground verification of the predictive benthic habitat map resulting from image classification showed that eight substrate classes were resolved with an overall accuracy of 69% down to a depth of 6 m, including live and dead coral framework. As compared to conventional from-image classification techniques, the reef-up method offers the potential for higher thematic accuracy while maintaining a greater degree of flexibility for repeat survey using platforms of higher spectral and spatial resolution, expected to come online in the near future. The fact that image acquisition and optical ground-truthing did not occur concurrently, is of particular relevance in confirming that in situ measurements can be made independent of image acquisition and retrospectively linked to appropriate substrate classes. Considering the wealth of hyperspectral data already acquired for shallow reef facies, the work highlights the potential of the reef-up approach for quantifying substrate distribution in coral environments using both air- and spaceborne platforms.

Habitat use and demographic population structure of elasmobranchs at a Caribbean atoll (Glover's Reef, Belize)

Abstract: A 5 yr spring and summer survey (July 2000 to May 2004) of the elasmobranch fauna of Glover's Reef Marine Reserve, Belize, documents the use of this oceanic atoll by at least 12 elasmo- branch species, including early life-stages of nurse sharks Ginglymostoma cirratum, Caribbean reef sharks Carcharhinus perezi, lemon sharks Negaprion brevirostris, and southern stingrays Dasyatis americana. Elasmobranch abundance was sampled in 3 atoll macrohabitats (deep lagoon, ocean reef, shallow lagoon) using standardized longlines. Total elasmobranch abundance did not change from year to year, but was significantly higher inside the lagoon than on the ocean reef outside the atoll. G. cirratum dominated both shallow and deep lagoon catches, with smaller individuals more preva- lent in the shallow lagoon. C. perezi of all size classes dominated the ocean reef catches, but small juveniles of this species were also common in the deep lagoon. This species rarely utilized the shal- low lagoon. A wide range of sizes of C. perezi and G. cirratum occupy Glover's Reef in spring and summer, with males maturing at 150 to 170 cm and 185 to 200 cm total length, respectively. The sex ratios of these species did not deviate from unity. A large juvenile Galapagos shark, C. galapagensis, was collected on the ocean reef, extending the range of this species into the Western Caribbean. Opportunistic surveys of fish markets on the Belize mainland revealed that inshore areas are utilized by early life-stages of sharks from the families Carcharhinidae (C. limbatus, N. brevirostris, Rhizo- prionodon porosus) and Sphyrnidae (Sphyrna tiburo, S. lewini, S. mokarran).

Usefulness and limits of biological dosimetry based on cytogenetic methods

Abstract: Damage from occupational or accidental exposure to ionising radiation is often assessed by monitoring chromosome aberrations in peripheral blood lymphocytes, and these procedures have, in several cases, assisted physicians in the management of irradiated persons. Thereby, circulating lymphocytes, which are in the G0 stage of the cell cycle are stimulated with a mitogenic agent, usually phytohaemagglutinin, to replicate in vitro their DNA and enter cell division, and are then observed for abnormalities. Comparison with dose-response relationships obtained in vitro allows an estimate of exposure based on scoring: Unstable aberrations by the conventional, well-established analysis of metaphases for chromosome abnormalities or for micronuclei; So-called stable aberrations by the classical G-banding (Giemsa-Stain-banding) technique or by the more recently developed fluorescent in situ hybridisation (FISH) method using fluorescent-labelled probes for centromeres and chromosomes. Three factors need to be considered in applying such biological dosimetry: (1) Radiation doses in the body are often inhomogeneous. A comparison of the distribution of the observed aberrations among cells with that expected from a normal poisson distribution can allow conclusions to be made with regard to the inhomogeneity of exposure by means of the so-called contaminated poisson distribution method; however, its application requires a sufficiently large number of aberrations, i.e. an exposure to a rather large dose at a high dose rate. (2) Exposure can occur at a low dose rate (e.g. from spread or lost radioactive sources) rendering a comparison with in vitro exposure hazardous. Dose-effect relationships of most aberrations that were scored, such as translocations, follow a square law. Repair intervening during exposure reduces the quadratic component with decreasing dose rate as exposure is spread over a longer period of time. No valid solution for this problem has yet been developed, although, in theory, both deterministic damage and aberrations might be repaired to a similar degree; a comparison of aberrations following a linear dose relationship might also help when the doses have been sufficiently large. (3) Investigations might have been possible only a certain time after the exposure. The relatively rapid disappearance of lymphocytes carrying unstable aberrations limits their use in retrospective dosimetry, years after exposure. Scoring stable aberrations, thought to persist in the circulating lymphocytes, might appear more appropriate in such situations. However, the examination of a representative number of cells by G-banding is extremely laborious, and the FISH method is not only expensive but has not yet been fully validated in different laboratories. In conclusion, biological dosimetry has serious limitations exactly for situations where the need for information is most urgent. It renders its most useful results when an individual has been exposed to a rather homogeneous high-level radiation over a short time interval, i.e. accidents at high-intensity radiation devices. On the other hand, it yielded less satisfactory information even when the most recent techniques were used for situations, where a low level, low dose rate exposure has occurred at some time in the past, for example for persons living in areas contaminated from the Chernobyl accident. Such negative experiences should be kept in mind in order to avoid futile and expensive investigations in the case of populations exposed from radioactivity and, notably, also from potentially clastogenic chemical agents.

Expression of vascular endothelial growth factor (VEGF) and its receptors in thyroid carcinomas of follicular origin: a potential autocrine loop.

Abstract: Objective: The aim of this study was to clarify the role of vascular endothelial growth factor (VEGF) and VEGF receptor (VEGFR) pathways in thyroid tumourigenesis. Methods: We examined VEGF, VEGFR-1 and VEGFR-2 expression on 34 papillary thyroid carcinomas (PTCs), 18 follicular thyroid carcinomas (FTCs), eight poorly differentiated thyroid carcinomas (PDTCs) and on a thyroid tumour-derived cell line (NPA 0 87) by immunohistochemistry, reverse transcriptase PCR, immunofluorescence and Western blotting. Results: We have demonstrated that VEGF expression was significantly (P , 0.05) more prevalent in PTCs (79%) than in FTCs (50%) or PDTCs (37%). Similarly, 76% of PTCs, 83% of FTCs and 25% of PDTCs expressed VEGFR-1, whereas 68% of PTCs, 56% of FTCs and 37% of PDTCs expressed VEGFR-2. Coexpression of VEGF and its receptors was observed in 50% of PTCs, 39% of FTCs and 12% of PDTCs, raising the possibility that VEGF may signal in an autocrine loop in these neoplasias, as observed previously for other types of cancer. In agreement with the idea that autocrine VEGF signalling plays an important role in thyroid carcinogenesis, the blockade of either VEGF or its receptors with neutralizing antibodies significantly reduced cell viability and increased apoptosis levels of the VEGFR-positive thyroid tumour cell line NPA 0 87. Conclusions: Our results highlight a previously undefined VEGF autocrine action in thyroid carcinomas which could play a crucial role in tumour cell survival and could represent a useful therapeutic target for thyroid tumours.

Product fit and consumer attitude toward brand extensions: the moderating role of product involvement

Abstract: It is proposed that product involvement provides a situational motivation for consumers to discount the importance of product fit in brand extension evaluations. An experimental study with multiple brand extensions was conducted to test this hypothesis. It is found that the hypothesis holds in the case of complementarity between parent brand and extension product. A personality variable, need for cognition (NFC) is further applied to test the underlying principle and results support the argument.

The impact of creativity on performance in non-profits

Abstract: This article examines how creative climate affects learning orientation and its relationship to organizational performance. The study also assesses creativity's link with market orientation, entrepreneurial orientation, and organizational flexibility. Past research on creativity climate has explored areas such as the arts, high-tech, information technology, media, and the sciences. The focus of this study is to assess creativity's role in managerial decision-making in the non-profit sector. Sound use of creativity can improve planning, implementation, and control by non-profit organization executives. Copyright © 2005 John Wiley & Sons, Ltd.

Endothelial nitric oxide synthase polymorphism, nitric oxide production, salt sensitivity and cardiovascular risk factors in Hispanics

Abstract: Mutations in the endothelial nitric oxide synthase (eNOS) gene may be associated with abnormal nitric oxide (NO) production and cardiovascular diseases. In this study, we investigated the prevalence of two eNOS polymorphisms, the Glu298Asp variant on exon 7, and the 4a/b variable number of tandem repeats (VNTR) on intron 4, and their association with blood pressure (BP), NO production, salt sensitivity and cardiovascular risk factors in healthy Venezuelans. The prevalence of both polymorphisms in Venezuelans was comparable to that described for Caucasians, but significantly different from that known for African-Americans and Japanese. The 4a/b genotype was associated with reduced levels of NO metabolites (25% decrease), larger BP lowering in response to salt restriction (9.0 vs 4.8 mmHg, P<0.05), greater prevalence of salt sensitivity (39% in 4a/b and 27% in 4b/b; P<0.05) and with higher LDL-cholesterol levels. The Glu298T polymorphism did not affect NO production, nor it was associated with salt sensitivity. Glu298Asp polymorphism was positively associated with higher weight, triglycerides and LDL-cholesterol. Neither polymorphism was associated with changes in fasting or postload serum glucose, BP, obesity and albuminuria. In conclusion, the prevalence of eNOS polymorphisms is strongly determined by ethnic factors. The 4a/b gene polymorphism could be a genetic susceptibility factor for the BP response to salt intake and for the genetic control of NO production. The reduced NO production in subjects with the 4a/b genotype may be responsible for the increased sensitivity of their BP to salt.

Academic and Behavioral Outcomes for Students at Risk for Emotional and Behavioral Disorders.

Abstract: The purpose of this study is to describe academic and behavioral outcomes for adolescents who were identified when they were in kindergarten and first grade as being at risk for developing emotional and behavioral disorders. Results indicated that primary school academic achievement and teacher ratings of academic competence were highly predictive of middle school reading achievement and moderately predictive of math achievement. Teacher ratings of behavior across time were consistent and reliable, and behavioral ratings by primary school teachers were predictive of students' behavioral ratings by middle school teachers. These findings suggest that young students with academic and behavioral problems continue to display problems into adolescence, placing them at serious risk for school failure and dropping out. Results have implications for early identification and prevention/intervention programs for at-risk students.