Is cardiac surgery warranted in children with Down syndrome? A case-controlled review

No Abstract. South African Medical Journal Vol. 96(9) (Part 2) 2006: 924-93

Why are some South African children with Down syndrome not being offered cardiac surgery?

No Abstract. South African Medical Journal Vol. 96(9) (Part 2) 2006: 914-91

Thoracic and Lumbar Vertebral Bone Mineral Density Changes in a Natural Occurring Dog Model of Diffuse Idiopathic Skeletal Hyperostosis

Ankylosing spinal disorders can be associated with alterations in vertebral bone mineral density (BMD). There is however controversy about vertebral BMD in patients wuse idiopathic skeletal hyperostosis (DISH). DISH in Boxer dogs has been considered a natural occurring disease model for DISH in people. The purpose of this study was to compare vertebral BMD between Boxers with and without DISH. Fifty-nine Boxers with (n=30) or without (n=29) DISH that underwent computed tomography were included. Vertebral BMD was calculated for each thoracic and lumbar vertebra by using an earlier reported and validated protocol. For each vertebral body, a region of interest was drawn on the axial computed tomographic images at three separate locations: immediately inferior to the superior end plate, in the middle of the vertebral body, and superior to the inferior end plate. Values from the three axial slices were averaged to give a mean Hounsfield Unit value for each vertebral body. Univariate statistical analysis was performed to identify factors to be included in a multivariate model. The multivariate model including all dogs demonstrated that vertebral DISH status (Coefficient 24.63; 95% CI 16.07 to 33.19; p <0.001), lumbar vertebrae (Coefficient -17.25; 95% CI -23.42 to -11.09; p < 0.01), and to a lesser extent higher age (Coefficient -0.56; 95% CI -1.07 to -0.05; p = 0.03) were significant predictors for vertebral BMD. When the multivariate model was repeated using only dogs with DISH, vertebral DISH status (Coefficient 20.67; 95% CI, 10.98 to 30.37; p < 0.001) and lumbar anatomical region (Coefficient -38.24; 95% CI, -47.75 to -28.73; p < 0.001) were again predictors for vertebral BMD but age was not. The results of this study indicate that DISH can be associated with decreased vertebral BMD. Further studies are necessary to evaluate the clinical importance and pathophysiology of this finding

Positivity of the English language

Over the last million years, human language has emerged and evolved as a fundamental instrument of social communication and semiotic representation. People use language in part to convey emotional information, leading to the central and contingent questions: (1) What is the emotional spectrum of natural language? and (2) Are natural languages neutrally, positively, or negatively biased? Here, we report that the human-perceived positivity of over 10,000 of the most frequently used English words exhibits a clear positive bias. More deeply, we characterize and quantify distributions of word positivity for four large and distinct corpora, demonstrating that their form is broadly invariant with respect to frequency of word use.Comment: Manuscript: 9 pages, 3 tables, 5 figures; Supplementary Information: 12 pages, 3 tables, 8 figure

Past Achievements and Future Challenges in 3D Photonic Metamaterials

Photonic metamaterials are man-made structures composed of tailored micro- or nanostructured metallo-dielectric sub-wavelength building blocks that are densely packed into an effective material. This deceptively simple, yet powerful, truly revolutionary concept allows for achieving novel, unusual, and sometimes even unheard-of optical properties, such as magnetism at optical frequencies, negative refractive indices, large positive refractive indices, zero reflection via impedance matching, perfect absorption, giant circular dichroism, or enhanced nonlinear optical properties. Possible applications of metamaterials comprise ultrahigh-resolution imaging systems, compact polarization optics, and cloaking devices. This review describes the experimental progress recently made fabricating three-dimensional metamaterial structures and discusses some remaining future challenges

Recognizing Speech in a Novel Accent: The Motor Theory of Speech Perception Reframed

The motor theory of speech perception holds that we perceive the speech of another in terms of a motor representation of that speech. However, when we have learned to recognize a foreign accent, it seems plausible that recognition of a word rarely involves reconstruction of the speech gestures of the speaker rather than the listener. To better assess the motor theory and this observation, we proceed in three stages. Part 1 places the motor theory of speech perception in a larger framework based on our earlier models of the adaptive formation of mirror neurons for grasping, and for viewing extensions of that mirror system as part of a larger system for neuro-linguistic processing, augmented by the present consideration of recognizing speech in a novel accent. Part 2 then offers a novel computational model of how a listener comes to understand the speech of someone speaking the listener's native language with a foreign accent. The core tenet of the model is that the listener uses hypotheses about the word the speaker is currently uttering to update probabilities linking the sound produced by the speaker to phonemes in the native language repertoire of the listener. This, on average, improves the recognition of later words. This model is neutral regarding the nature of the representations it uses (motor vs. auditory). It serve as a reference point for the discussion in Part 3, which proposes a dual-stream neuro-linguistic architecture to revisits claims for and against the motor theory of speech perception and the relevance of mirror neurons, and extracts some implications for the reframing of the motor theory

Toward Human-Carnivore Coexistence: Understanding Tolerance for Tigers in Bangladesh

Fostering local community tolerance for endangered carnivores, such as tigers (Panthera tigris), is a core component of many conservation strategies. Identification of antecedents of tolerance will facilitate the development of effective tolerance-building conservation action and secure local community support for, and involvement in, conservation initiatives. We use a stated preference approach for measuring tolerance, based on the ‘Wildlife Stakeholder Acceptance Capacity’ concept, to explore villagers’ tolerance levels for tigers in the Bangladesh Sundarbans, an area where, at the time of the research, human-tiger conflict was severe. We apply structural equation modeling to test an a priori defined theoretical model of tolerance and identify the experiential and psychological basis of tolerance in this community. Our results indicate that beliefs about tigers and about the perceived current tiger population trend are predictors of tolerance for tigers. Positive beliefs about tigers and a belief that the tiger population is not currently increasing are both associated with greater stated tolerance for the species. Contrary to commonly-held notions, negative experiences with tigers do not directly affect tolerance levels; instead, their effect is mediated by villagers’ beliefs about tigers and risk perceptions concerning human-tiger conflict incidents. These findings highlight a need to explore and understand the socio-psychological factors that encourage tolerance towards endangered species. Our research also demonstrates the applicability of this approach to tolerance research to a wide range of socio-economic and cultural contexts and reveals its capacity to enhance carnivore conservation efforts worldwide

How managers can build trust in strategic alliances: a meta-analysis on the central trust-building mechanisms

Trust is an important driver of superior alliance performance. Alliance managers are influential in this regard because trust requires active involvement, commitment and the dedicated support of the key actors involved in the strategic alliance. Despite the importance of trust for explaining alliance performance, little effort has been made to systematically investigate the mechanisms that managers can use to purposefully create trust in strategic alliances. We use Parkhe’s (1998b) theoretical framework to derive nine hypotheses that distinguish between process-based, characteristic-based and institutional-based trust-building mechanisms. Our meta-analysis of 64 empirical studies shows that trust is strongly related to alliance performance. Process-based mechanisms are more important for building trust than characteristic- and institutional-based mechanisms. The effects of prior ties and asset specificity are not as strong as expected and the impact of safeguards on trust is not well understood. Overall, theoretical trust research has outpaced empirical research by far and promising opportunities for future empirical research exist

Human lung cancer cells express functionally active Toll-like receptor 9

BACKGROUND: CpG-oligonucleotides (CpG-ODN), which induce signaling through Toll-like receptor 9 (TLR9), are currently under investigation as adjuvants in therapy against infections and cancer. CpG-ODN function as Th-1 adjuvants and are able to activate dendritic cells. In humans TLR9 has been described to be strongly expressed in B-lymphocytes, monocytes, plasmacytoid dendritic cells and at low levels in human respiratory cells. We determined whether a direct interaction of bacterial DNA with the tumor cells themselves is possible and investigated the expression and function of TLR9 in human malignant solid tumors and cell lines. TLR9 expression by malignant tumor cells, would affect treatment approaches using CpG-ODN on the one hand, and, on the other hand, provide additional novel information about the role of tumor cells in tumor-immunology. METHODS: The expression of TLR9 in HOPE-fixed non-small lung cancer, non-malignant tissue and tumor cell lines was assessed using immunohistochemistry, confocal microscopy, in situ hybridization, RT-PCR and DNA-sequencing. Apoptosis and chemokine expression was detected by FACS analysis and the Bio-Plex system. RESULTS: We found high TLR9 signal intensities in the cytoplasm of tumor cells in the majority of lung cancer specimens as well as in all tested tumor cell lines. In contrast to this non-malignant lung tissues showed only sporadically weak expression. Stimulation of HeLa and A549 cells with CpG-ODN induced secretion of monocyte chemoattractant protein-1 and reduction of spontaneous and tumor necrosis factor-alpha induced apoptosis. CONCLUSIONS: Here we show that TLR9 is expressed in a selection of human lung cancer tissues and various tumor cell lines. The expression of functionally active TLR9 in human malignant tumors might affect treatment approaches using CpG-ODN and shows that malignant cells can be regarded as active players in tumor-immunology

The action of a multidisciplinary team in the nutritional care of critically ill patients

Hospitalized patients may have special nutrient requirements imposed by a combination of malnutrition and enhanced utilization of nutrients resulting from the disease process. Nutritional support, mainly during critical stages of disease, should be provided safely and effectively. Several studies have evaluated the paper of a multidisciplinary team in the administration of a nutritional therapy. Individually, the majority of these studies are underpowered to evaluate an effect on the quality of nutritional care. With the objective to identify problems inherent to the supply of nutritional support to hospitalized patients and verify the impact of the actions of a multidisciplinary team on the quality of these procedures, we analysed articles that have been published between 1980 and 2004 about the role of the action of multidisciplinary teams in the care and nutritional outcome of hospitalized patients, especially those undergoing intensive care. The terms used for the search were: multidisciplinary team, nutritional support, parenteral nutrition, enteral feeding, critically ill, intensive care unit, critically ill child. Of 130 studies, intially identified, just 24 were selected, of which 14 compared the standard of nutritional therapy with and without the presence of a multidisciplinary team. The inadequate supply of nutrients, infection and metabolic complications and the excessive use of parenteral nutrition were the main problems detected in the supply of nutritional support to hospitalized patients. In the comparative studies, the presence of the multidisciplinary team improved the pattern of nutritional support, and reduced the incidence of complications and the costs.Pacientes hospitalizados podem ter necessidades nutricionais especiais em função da desnutrição e dos desequilíbrios metabólicos impostos pelas doenças. A terapia nutricional, principalmente nos estágios críticos das enfermidades, deve ser administrada de modo seguro e eficaz. Vários estudos têm avaliado o papel da equipe multidisciplinar na administração da terapia nutricional. Com o objetivo de identificar os problemas inerentes à administração da terapia nutricional em pacientes hospitalizados e verificar o impacto da atuação de uma equipe multidisciplinar na qualidade dos procedimentos, foi realizada uma revisão que analisou artigos publicados entre 1980 e 2004 sobre o papel da atuação de equipes multidisciplinares no cuidado e na evolução nutricional de pacientes hospitalizados, principalmente os que se encontravam sob cuidados intensivos. Os termos utilizados na pesquisa foram: multidisciplinary team, nutritional support, parente-ral nutrition, enteral feeding, critically ill, intensive care unit,critically ill child. Dos 130 estudos inicialmente identificados, foram selecionados 24, dos quais 14 compararam o padrão de terapia nutricional com e sem a presença da equipe multidisciplinar. Os principais problemas detectados na administração de terapia nutricional em pacientes hospitalizados foram a oferta inadequada de nutrientes, as complicações infecciosas e metabólicas e o uso excessivo de nutrição parenteral. Nos estudos comparativos, a presença da equipe multidisciplinar melhorou o padrão de oferta nutricional, reduziu a incidência de complicações e os custos.Universidade Federal de São Paulo (UNIFESP) Departamento de PediatriaHospital São Paulo Unidade de Cuidados Intensivos PediátricosHospital São Paulo Equipe Multidisciplinar de Terapia NutricionalUNIFESP, Depto. de PediatriaHospital São Paulo Unidade de Cuidados Intensivos PediátricosHospital São Paulo Equipe Multidisciplinar de Terapia NutricionalSciEL