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PubMed2004

ECLAMC: the Latin-American collaborative study of congenital malformations.

DEFINITION: ECLAMC ('Estudio Colaborativo Latino Americano de Malformaciones Congenitas') is a program for the clinical and epidemiological investigation of risk factors in the etiology of congenital anomalies in Latin-American hospitals, using a case-control methodological approach. It is a voluntary agreement among professionals lacking institutional base as well as designated budgets. ECLAMC has been usually funded by research-funding agencies rather than public health ministries. The National Research Councils of Argentina and Brazil have been the main sources of support during its 36 years of existence. Since vital and health statistics are unreliable in South America, ECLAMC collects all the information required for the denominators in a hospital-based sample of births. ECLAMC can be defined as a continental network of persons interested in research and prevention of birth defects. HISTORY AND EVOLUTION: From the institutional point of view, ECLAMC has had headquarters in diverse centers of Argentina and Brazil, but always as an independent research project, without a defined administrative link. ECLAMC began operating in 1967, as an investigation limited to the city of Buenos Aires, Argentina, and it gradually expanded until covering all the 10 countries of South America as well as Costa Rica and the Dominican Republic. Even though ECLAMC has maintained essentially the same original experimental design since 1967, due to the data accumulated by the program, the increasing experience as well as the development in science, technical modifications occurred including a DNA bank and a fully informatized data handling system. Since 1974 ECLAMC has been a founder member of the International Clearinghouse for Birth Defects Monitoring Systems; since 1994 a WHO Collaborating Center for the Prevention of Congenital Malformations, and since 2000 a collaborating member of the NIH Global Netwok for Women's and Children's Health Research. METHODOLOGY: The maternity hospital network of ECLAMC examines around 200,000 births per year. All major and minor anomalies diagnosed at birth in infants weighing 500 g or more are registered according to a manual of procedures. The next non-malformed baby of the same sex born in the same hospital is selected as a control subject for each case. Thus, a one-to-one healthy control group matched by sex, time and place of birth is obtained. As a system of epidemic surveillance, ECLAMC systematically observes the fluctuations in the frequencies of different malformations and, in the case of an alarm for a probable epidemic of a given malformation, at a given moment, and given area, it acts to identify its cause. As termination of pregnancy has severe legal restrictions in South America, prevention of birth defects should concentrate on primary, preconceptional and tertiary measures. Tertiary measures aim to avoid complications of the affected patients from the medical, psychological, and social standpoints.

Biomedical Research↗
PubMedDate not supplied

The Canadian Heart Health Initiative: dissemination perspectives.

The Canadian Heart Health Initiative is a country-wide strategy for the prevention of cardiovascular disease. Initiated with a 15-year horizon, it has resulted in extensive networks and coalitions involving Health Canada, the 10 provincial departments of health and over 1,000 organizations. There are five phases: policy development through country-wide consultations (1986-88); provincial heart health surveys (1986-91); research demonstration programs (1989-97); and evaluation (1994-97). The dissemination research phase studies the adoption of interventions by communities and health systems. As a paradigm for dissemination of health policy, some key features of the Initiative are translation of the science base in prevention into community programs; consensual policy development; federal and provincial co-funding arrangements; key role played by the public health system; capacity building; organization and management model linking activities at the national, provincial and community levels. The methodologies and capacities developed are applicable to other health promotion and disease prevention areas.

Canada↗
PubMed1993

The colony stimulating factors.

Hematopoiesis is a dynamic process, which generate in the range of 10(9) cells/kg each day of erythroid and myeloid cells respectively. In vitro assays that were developed 20 years ago, have been used to define factors that can stimulate growth and differentiation of bone marrow (BM) derived progenitor cells. These growth factors for hematopoiesis were termed Colony Stimulating Factors (CSFs) since the assay system was to induce colonies. With the application of molecular biologic approaches, the genes encoding for these CSFs have been localized and cloned. Production of CSFs and other soluble signal substances (cytokines) as pure proteins have led to important insights into how hematopoiesis is regulated by a complex network made up by interactions between cells and cytokines. The availability of CSFs in clinically useful amounts has also led to clinical trials with new strategies for treating hematopoietic dysfunctions, congenital or acquired. Because others have recently reviewed clinical applications or basic science studies on the colony stimulating factors, we will summarize the two with focus on common features between the different CSFs.

Animals↗
PubMed2004

Participation of primary motor cortical neurons in a distributed network during maze solution: representation of spatial parameters and time-course comparison with parietal area 7a.

Traditionally, primary motor cortex (M1) has been thought to be involved solely in planning and generating movements. Recent evidence suggests that the arm area of M1 plays a role in other functions, such as the representation of serial order (Pellizzer et al. 1995, Science 269:702-705; Carpenter et al. 1999, Science 283:1752-1757) and spatial processing (Georgopoulos et al. 1989, Science 243:234-236). Previous studies of such cognitive processes have used tasks in which a directed arm movement was required, raising a question as to whether this brain area is involved in cognitive processing per se, or whether such cognitive signals may be gated into the arm area of M1 only when arm movements are required. To study this question, we developed a task that required a spatial analysis of a complex visual stimulus, but required no arm movement as a response. In this task, monkeys were shown an octagonal maze. After an imposed delay of 2 to 2.5 s, they indicated whether a path that emanated from the center of the maze exited at the perimeter (exit maze) or terminated within the maze (no-exit maze) by pressing a pedal with their left or right foot, respectively. We recorded from 785 cells from the arm area of M1 from two monkeys during the delay period of the maze task. We found that cell activity was influenced by both the exit status and the direction of the path, beginning soon after the maze was displayed. This activity was not related to the activation of arm muscles, suggesting that the directional signals observed represented abstract spatial aspects of maze processing. Finally, we compared maze-related activity of M1 neurons with those recorded from posterior parietal area 7a, reported previously (Crowe et al. 2004). Interestingly, cells from each area exhibited similar properties. Both the exit status and path direction were encoded by cells in M1 and 7a, although to different extents. An analysis of the time-course of the neural representation of these factors revealed that area 7a and M1 begin to encode these factors at the same time, suggesting these brain areas are part of a distributed system performing the spatial computations involved in maze solution.

Action Potentials↗
PubMed1996

Merging Back-propagation and Hebbian Learning Rules for Robust Classifications.

By imposing saturation requirements on hidden-layer neural activations, a new learning algorithm is developed to improve robustness on classification performance of a multi-layer Perceptron. Derivatives of the sigmoid functions at hidden-layers are added to the standard output error with relative significance factors, and the total error is minimized by the steepest-descent method. The additional gradient-descent terms become Hebbian, and this new algorithm merges two popular learning algorithms, i.e., error back-propagation and Hebbian learning rules. Only slight modifications are needed for the standard back-propagation algorithm, and additional computational requirements are negligible. This saturation requirement effectively reduces output sensitivity to the input, which results in improved robustness and better generalization for classifier networks. Also distributed representations at hidden-layers are successfully suppressed to accomplish efficient utilization of hidden neurons. Computer simulations demonstrates much faster learning convergence as well as improved robustness for classifications and hetero-associations of binary patterns. Copyright 1996 Elsevier Science Ltd

Journal Article↗
PubMed2005

Linking epithelial-mesenchymal transition to the well-known polarity protein Par6.

Epithelial-mesenchymal transition (EMT) is involved in the formation of the body plan, tissue remodeling, and cancer progression. Two recent reports in Science (Barrios-Rodiles et al., 2005; Ozdamar et al., 2005) have decisively advanced our understanding of EMT. Par6 was identified as a key player in the control of tight junction (TJ) stability. This new study provides further insight into the protein networks involved in topologically regulated control of epithelial cell polarity and plasticity.

Adaptor Proteins, Signal Transducing↗
PubMed2001

Network thermodynamics and complexity: a transition to relational systems theory.

Most systems of interest in today's world are highly structured and highly interactive. They cannot be reduced to simple components without losing a great deal of their system identity. Network thermodynamics is a marriage of classical and non-equilibrium thermodynamics along with network theory and kinetics to provide a practical framework for handling these systems. The ultimate result of any network thermodynamic model is still a set of state vector equations. But these equations are built in a new informative way so that information about the organization of the system is identifiable in the structure of the equations. The domain of network thermodynamics is all of physical systems theory. By using the powerful circuit simulator, the Simulation Program with Integrated Circuit Emphasis (SPICE), as a general systems simulator, any highly non-linear stiff system can be simulated. Furthermore, the theoretical findings of network thermodynamics are important new contributions. The contribution of a metric structure to thermodynamics compliments and goes beyond other recent work in this area. The application of topological reasoning through Tellegen's theorem shows that a mathematical structure exists into which all physical systems can be represented canonically. The old results in non-equilibrium thermodynamics due to Onsager can be reinterpreted and extended using these new, more holistic concepts about systems. Some examples are given. These are but a few of the many applications of network thermodynamics that have been proven to extend our capacity for handling the highly interactive, non-linear systems that populate both biology and chemistry. The presentation is carried out in the context of the recent growth of the field of complexity science. In particular, the context used for this discussion derives from the work of the mathematical biologist, Robert Rosen.

Biological Transport↗
PubMed2003

Global information network on chemicals (GINC) and its Asian component.

The Global Information Network on Chemicals (GINC) is an effort to build a global information network that links international, national, and other organizations working for the safe management of chemicals in order to exchange information and improve communications. The project was originally proposed in 1993 by one of the authors then at the National Institute of Health Sciences (NIHS) of Japan to the International Program on Chemical Safety (IPCS), which is a joint project of World Health Organization (WHO), International Labor Organization (ILO), and United Nations Environment Program (UNEP). The base support system was first implemented at NIHS using the Internet/World Wide Web (WWW) technology in 1995. The project was then endorsed by the Intergovernmental Forum on Chemical Safety (IFCS) and was adopted by the Inter-Organization Program for the Sound Management of Chemicals (IOMC). However, the base system (http://www.nihs.go.jp/GINC/index.html) has been developed and maintained solely by the NIHS group under the support of the Ministry of Health and Welfare (MHW), Japan. Asia, particularly East Asia and the Pacific region, was chosen as the feasibility study region for this project. During the period from December 1994 to July 2002, NIHS hosted eight meetings on this project held in Tokyo.

Asia↗
PubMed2002

Technical innovations in international e-nursing.

Saudi Arabia faces a severe shortage of nurses. An online nursing degree is being introduced as one approach to this problem. In 1999, the College of Nursing and Health Science at George Mason University formed a strategic partnership with IMED Link, a private telehealth company, to deliver online nursing education. Nine courses have been developed so far, including nursing assessment. The educational material will be distributed via Saudi Arabia's telemedicine network. The courses will be led by professors of nursing at George Mason University using videoconferencing, coupled with online computer classes and Internet tools. Both nursing content and expertise in Web technologies are necessary to develop a successful e-nursing programme.

Curriculum↗
PubMed2003

History of academic general and ambulatory pediatrics.

Academic general pediatrics and ambulatory care are closely linked to the development of the Ambulatory Pediatric Association, an organization with nearly 2000 members active in teaching, patient care, and research. Primary care, behavioral-developmental pediatrics, prevention, health promotion, community pediatrics, socioeconomic issues, cultural and ethnic diversity, advocacy, research in education, social issues, and environmental health lie within the purview of general pediatrics. In part, because of their teaching and patient care obligations, but also due to a lack of fellowship research training, many general pediatrics faculty have had difficulty in accomplishing significant research. By supporting fellowship training in general pediatrics, The Robert Wood Johnson Foundation General Pediatrics Academic Development Program and the current fellowship program supported by the Bureau of Health Manpower are important efforts to remedy this deficiency. The sciences basic to general pediatrics research include epidemiology, biostatistics, and the behavioral sciences. In addition, general pediatrics research often borrows from other sciences and collaborates with investigators in other disciplines. Partnerships between general pediatrics divisions and practicing pediatricians for teaching and research, e.g. the Community Education in Community Settings program, provides a realistic educational program for future pediatricians. The Pediatric Research in Office Setting network is another important vehicle for translation of research into the practice of general pediatrics. The steady growth of the Ambulatory Pediatric Association over the past four decades is testimony to the creativity, adaptability, and verve that has characterized the discipline of general pediatrics.

Ambulatory Care↗
PubMed2001

The dream's navel between chaos and thought.

The authors begin by drawing attention to the problem of the transition from the biological to the psychic, noting that Freud himself, with his background in the neurosciences, grappled with it throughout his career. Certain recent paradigms more commonly applied to the natural sciences, such as in particular chaos and complexity theory, can in their view prove fruitful in psychoanalysis too, and it is shown how these notions are inherent in some of Freud's conceptions. The unconscious is stated to operate like a neural network, performing the kind of parallel processing used in the computing of highly complex situations, whereas the conscious mind is sequential. Dreams, in the authors' opinion, are organisers of the mind, imparting order to the turbulence of the underlying wishes and unconscious fantasies and structuring them through the dream work. Through dreams, the structured linearity of conscious thought can emerge out of the non-linear chaos of the drives. The dream's navel can be seen as the chaotic link, or interface, between the unconscious wish, which constitutes an attractor, and the conscious thought. The attractor may be visualised as having an hourglass or clepsydra shape, the narrow section being the dream's navel, and, being the same at any scale of observation, has the property of fractality.

Dreams↗
PubMed1998

English historical demography and the nuptiality conundrum: new perspectives.

"In the last decade, nuptiality has been placed at the centre of the English demographic regime in the long eighteenth-century. Proto-industrial areas in particular are increasingly seen to have experienced substantial decline in the female age at first marriage during this period, helping to fuel substantial population growth. This article uses family reconstitution and other data to question the uniformity of this experience and to suggest new avenues of interpretation rather than simply observation. For Calverley in West Yorkshire, England, female marriage ages remained stable throughout the proto-industrialisation process. More significantly, the distribution of marriage ages around the mean was much narrower than similar measures elsewhere. The article suggests that kinship, a deep sentimental and practical attachment to land, and an early retirement system lay behind this experience."

Demography↗
PubMed2004

Community partnerships: the cornerstone of community health research.

Community partnerships have been recognized as the cornerstone of community research. The recent Institute of Medicine report, Unequal Treatment, puts forth the idea of creating community partnerships as a strategy to address racial and ethnic disparities in health care. Community-based research is frequently reported in the literature as a study conducted in the community versus with the community. The objective of this review is to examine models of community partnerships, to consider their implications for community-based research, and to identify directions for future nursing research.

Community Health Nursing↗
PubMed1986

[Limits of conventional nutrition education: an example from a West African urban area].

The failure of conventional nutrition education, as practiced in Western Africa, is acknowledged by the author. This assessment follows the formative and summative evaluation of a nutrition education programme, directed towards the parents of hospitalized children, in a hospital, in the Ivory Coast. Often carried out within conventional health structures (maternal-child health centers, rural health centers, hospitals, etc...), the programme represents an addition to daily health care activities, with actions often too isolated and too limited to exert a decisive impact on public health. Most of the time, these programmes are conceived and implemented by health care workers who are inadequately motivated and trained in both nutrition and education. Poorly conceived messages that lack cultural, economic or social adaptation to the specified target population, authoritarian, unfeeling pedagogy, and inadequate educational tools lead to uncertain results. Results that are difficult to assess due to the absence of a clear definition of objectives and procedures for scientific evaluation. The author, in agreement with other recent studies, suggests that nutrition education should be viewed as the cumulative effect of all the various communication activities aimed at modifying those individual or community behaviours that affect the nutritional status of a given population. Multimedia nutrition education, however, can only be implemented once population needs and available communication channels have been identified. It is with the idea of promoting such multimedia activities that the network for nutrition education in Africa has been created (see p. 56).

Cote d'Ivoire↗
PubMed2006

Contribution to the knowledge of the veterinary science and of the ethnobotany in Calabria region (Southern Italy).

BACKGROUND: A series of preliminary research projects on plants used in Calabria (Southern Italy) in veterinary science and in other ethno-botanical fields (minor nourishment, domestic and handicraft sector) was carried out in the last twenty years. From the ethno-botanical point of view, Calabria is one of the most interesting region, since in the ancient times it was subject to the dominant cultures of several people (Greeks, Romans, Byzantines, Arabs, Normans etc.). Until some decades ago the road network was poorly developed and villages were isolated, so that the culture of the "subsistence" and some archaic customs were kept. METHODS: Data were collected by means of "open" interviews to farmers, shepherds and housewives in the last twenty years. More than 100 informants were interviewed, mostly over 50 years old. Plants were identified by local informants through gathering in the area or through examination of the fresh plants collected by the researchers. The collected data were compared with pharmacobotanical papers mainly of southern Italy and with other studies, in order to highlight novelties or concordances of uses. RESULTS: The use of 62 taxa distributed into 34 families are described. Among these, 8 are or were employed in veterinary science, 8 as anti-parasitic agents, 19 in minor nourishment, 5 as seasoning, 38 for other uses. Some toxic species for cattle are also mentioned. CONCLUSION: Among the major findings: the use of Helleborus bocconei for bronchitis of bovines and of Scrophularia canina for lameness in veterinary science; Nerium oleander and Urginea maritima as anti-parasitic agents; Epilobium angustifolium, Centaurea napifolia L. and C. sphaerocephala L. in minor nourishment.

Aged↗
PubMed2003

Interactive instruction of cellular physiology for remote learning.

The biomedical sciences are a rapidly changing discipline that have adapted to innovative technological advances. Despite these many advances, we face two major challenges: a) the number of experts in the field is vastly outnumbered by the number of students, many of whom are separated geographically or temporally and b) the teaching methods used to instruct students and learners have not changed. Today's students have adapted to technology--they use the web as a source of information and communicate via email and chat rooms. Teaching in the biomedical sciences should adopt these new information technologies (IT), but has thus far failed to capitalize on technological opportunity. Creating a "digital textbook" of the traditional learning material is not sufficient for dynamic processes such as cellular physiology. This paper describes innovative teaching techniques that incorporate familiar IT and high-quality interactive learning content with user-centric instruction design models. The Virtual Labs Project from Stanford University has created effective interactive online teaching modules in physiology (simPHYSIO) and delivered them over broadband networks to their undergraduate and medical students. Evaluation results of the modules are given as a measure of success of such innovative teaching method. This learning media strategically merges IT innovations with pedagogy to produce user-driven animations of processes and engaging interactive simulations.

Biology↗