585 research outputs found
Detection of C-type natriuretic peptide (CNP) transcript in the rat heart and immune organs
Previous studies suggested the expression of mRNA, coding for CNP, exclusively in the central nervous system. In the present study, using the polymerase chain reaction (PCR) technique instead of the less sensitive Northern blot hybridization, CNP-specific sequences have also been detected in rat atria and ventricles of the heart as well as in organs of the immune system (thymus, spleen and lymph nodes). Parallel PCR-assays documented ANP-mRNA in these tissues. To verify specificity of the PCR-products, Southern blots have been hybridized with a third internal oligonucleotide and amplification products have been sequenced. The relative level of CNP-mRNA in these tissues was estimated to be in the range of 1-9% of total brain CNP transcripts. The results suggest that the peptide may have a peripheral as well as a central site of action. In light of its pronounced effect on cell proliferation, particular interest should focus on a possible role of CNP in the immune system
Transcription of brain natriuretic peptide and atrial natriuretic peptide genes in human tissues
We have compared the expression of atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) genes in various human tissues using a quantitative polymerase chain reaction technique. Tissues of three human subjects, obtained at autopsy, were analyzed. BNP transcripts could be detected in the central nervous system, lung, thyroid, adrenal, kidney, spleen, small intestine, ovary, uterus, and striated muscle. ANP transcripts could also be demonstrated in various human extracardiac tissues including several endocrine organs. In all peripheral tissues, the level of both natriuretic peptide transcripts was approximately 1-2 orders of magnitude lower than in cardiac ventricular tissues. This distribution is in marked contrast to the much lower level of ANP and BNP transcripts present in extracardiac rat tissues (generally less than 1/1000 of ventricles). These data suggest differential expression of the two natriuretic peptide genes in cardiac and extracardiac tissues in man. Furthermore, the presence of local synthesis of ANP and BNP in various peripheral organs suggests paracrine and/or autocrine function of these natriuretic peptides
When Words Become Unclear : Unmasking ICT Through Visual Methodologies in Participatory ICT4D
Across the globe, our work and social lives are increasingly integrated with Information and Communication Technologies (ICT), yet massive disparities in the values, uses and benefits of ICT exist. New methods are needed to shed light on unique and integrative concepts of ICT across cultures. This paper explores the use of visual methods to facilitate critical engagement with ICT—defined as situational awareness, reflexive ICT practice and power and control over ICT. This definition of critical ICT engagement is informed by a cultural identity lens, and intends to improve participatory methods in ICT for Development (ICT4D) and community technology design and application. Our notion of critical ICT engagement is developed through an analysis of three case studies, each employing visual methods to shed light on concepts and practices of ICT cross-culturally. This paper makes three contributions to the ICT4D literature. First, it establishes a cultural identity lens to chart out cultural differences between researchers and participants, and to develop situational awareness of ICT in context. Second, it defines the conceptual domain of reflexive ICT practice and establishes the key role of researchers in facilitating it. Third, it argues for the need to support participants to develop capacity to engage critically with ICT as a means to influence social and organizational structures. This paper offers a way for researchers and practitioners to engage with cultural issues in community-based research and design using visual methodologies
- …