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1.
J Microsc ; 228(Pt 2): 132-8, 2007 Nov.
Article in English | MEDLINE | ID: mdl-17970913

ABSTRACT

Point Spread Function (PSF) modelling is an important task in image formation analysis. In confocal microscopy, the exact PSF is rarely known, thus one has to rely on its approximation. An initial estimation is usually performed experimentally by measuring fluorescent beads or analytically by studying properties of the optical system. Yet, fluorescent line-scanning confocal microscopes are not widespread; therefore, very few adapted models are available in the literature. In this paper, we propose an analytical PSF model for line-scanning confocal microscopes. Validation is performed by measuring the error between our model and an experimental PSF measured with fluorescent beads, assumed to represent the real PSF. Comparison with existing models is also presented.

2.
Cell Mol Biol (Noisy-le-grand) ; 52(6): 32-7, 2007 Jan 20.
Article in English | MEDLINE | ID: mdl-17543207

ABSTRACT

Some recent works on intercellular communication pointed out an impaired trafficking of Cx43 proteins in early carcinogenesis. In collaboration with biologists, we propose an automatic system for the analysis of spatial protein configurations within cells at early tumor stages. This system is an essential step towards the future development of a computer-aided diagnosis tool and the statistical validation of biological hypotheses about Cx43 expressions and configurations during tumorogenesis. The proposed system contains two dependent part: a segmentation part in which the cell structures of interest are automatically located on images and a characterization part in which some spatial features are computed for the classification of cells. Using immunofluorescent images of cells, the nucleus, cytoplasm and proteins structures within the cell are extracted. Then, some spatial features are computed to characterize spatial configurations of the proteins with regard to the nucleus and cytoplasm areas in the image. Last, the 3D cell images are classified into pathogenic or viable classes. The system has been quantitatively evaluated over 60 cell images acquired by a deconvolution high-resolution microscope and whose ground truth has been manually given by a biologist expert. As a perspective, a 3D spatial reasoning and visualization module is currently under development.


Subject(s)
Cell Communication/physiology , Connexin 43/metabolism , Image Interpretation, Computer-Assisted , Imaging, Three-Dimensional , Neoplasms/physiopathology , Pattern Recognition, Automated/methods , Fluorescent Dyes/metabolism , Humans , Image Interpretation, Computer-Assisted/instrumentation , Image Interpretation, Computer-Assisted/methods , Imaging, Three-Dimensional/instrumentation , Imaging, Three-Dimensional/methods , Neoplasms/pathology
3.
J Biosoc Sci ; 30(2): 193-225, 1998 Apr.
Article in English | MEDLINE | ID: mdl-9746825

ABSTRACT

This paper reviews the results of clinical trials and community studies of lactational amenorrhoea and its role as a contraceptive method (LAM). Indicators which are used in efficacy trials and effectiveness interventions are compared and sets of indicators of effectiveness appropriate to community-based LAM programmes are recommended. A five-tiered ecological framework is used to facilitate selection of indicators which range from individual to policy level outcomes. The indicator framework is intended as a tool for health practitioners in family planning and maternal and child health service delivery settings who are interested in designing programmatic interventions for the promotion of LAM, particularly among less well-educated women of lower socioeconomic communities.


PIP: If lactational amenorrhea (LAM) is to reach its full potential as a method of child spacing, additional programmatic interventions must be conducted at the community level--especially in developing countries--to demonstrate its effectiveness. A review of clinical trials and community studies of LAM conducted both before and after the Bellagio Consensus Conference was undertaken in order to develop a set of indicators for the effectiveness of LAM promotion efforts under a range of field conditions. The resultant framework is intended as a tool for health professionals in family planning and maternal-child health service delivery settings who are interested in designing community-based LAM programs. A 5-tiered (individual, interpersonal, community, health system, and macro-policy factors) ecological systems model was used as the framework for indicator development. Laboratory, physiological, and behavioral measures were rated and weighted according to their scientific rigor (quality of data collected, technical feasibility), administrative feasibility (cost to administer, time required and likelihood of compliance), and community appropriateness (cultural sensitivity, contribution to women's knowledge and skills). Included among the suggested indicators are hormonal levels in urine or blood samples, timing of first vaginal bleed, duration of breast feeding, use of pacifiers or nipples, breast feeding knowledge and cultural influences, number of breast feeds per 24 hours, and frequency of intercourse.


Subject(s)
Amenorrhea , Breast Feeding , Contraception Behavior/psychology , Lactation/physiology , Community Health Planning , Family Planning Services , Female , Guidelines as Topic , Humans
4.
J Health Popul Dev Ctries ; 1(1): 68-84, 1997.
Article in English | MEDLINE | ID: mdl-12293262

ABSTRACT

PIP: Exclusive and extended breast feeding is responsible for much of the fertility limitation and child spacing throughout the world. In many developing countries, where breast feeding is almost universal and of long duration, postpartum amenorrhea protects women from closely spaced subsequent pregnancies. However, at the same time, increased pressures toward modernization, rapid rural-to-urban migration, frequent advertisements of powdered milk substitutes, and the increased employment of women outside of the home are adversely affecting traditional breast feeding practices. In Bolivia, almost all women breast feed their newborn infants, for periods up to 2 years. This paper reports findings which describe and compare patterns of women's differential knowledge of breast feeding and lactational amenorrhea resulting from data collection using a survey instrument and a focus group guide. The findings are part of a larger study on infant feeding and child spacing conducted in periurban communities in Bolivia. Current and historical trends with regard to paradigm and methodology in social science research are reviewed and the survey/focus group research method is described.^ieng


Subject(s)
Amenorrhea , Breast Feeding , Family Planning Services , Focus Groups , Knowledge , Lactation , Methods , Nutrition Surveys , Urban Population , Americas , Bolivia , Data Collection , Demography , Developing Countries , Health , Infant Nutritional Physiological Phenomena , Latin America , Nutritional Physiological Phenomena , Population , Population Characteristics , Postpartum Period , Reproduction , Research , South America
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