Anisotropic expansion of hepatocyte lumina enforced by apical bulkheads.

Lumen morphogenesis results from the interplay between molecular pathways and mechanical forces. In several organs, epithelial cells share their apical surfaces to form a tubular lumen. In the liver, however, hepatocytes share the apical surface only between adjacent cells and form narrow lumina that grow anisotropically, generating a 3D network of bile canaliculi (BC).

Specificities of exosome versus small ectosome secretion revealed by live intracellular tracking of CD63 and CD9.

Despite their roles in intercellular communications, the different populations of extracellular vesicles (EVs) and their secretion mechanisms are not fully characterized: how and to what extent EVs form as intraluminal vesicles of endocytic compartments (exosomes), or at the plasma membrane (PM) (ectosomes) remains unclear. Here we follow intracellular trafficking of the EV markers CD9 and CD63 from the endoplasmic reticulum to their residency compartment, respectively PM and late endosomes. We observe transient co-localization at both places, before they finally segregate.

Localized Intercellular Transfer of Ephrin-As by Trans-endocytosis Enables Long-Term Signaling.

Ephrins can elicit either contact-mediated cell-cell adhesion or repulsion, depending on the efficiency of the removal of their ligand-receptor complexes from the cell surface, thus controlling tissue morphogenesis and oncogenic development. However, the dynamic of the turnover of newly assembled ephrin-Eph complexes during cell-cell interactions remains mostly unexplored. Here, we show that ephrin-A1-EphA2 complexes are locally formed at the tip of the filopodia, at cell-to-cell contacts.

Sexual and reproductive health for young adults in Colombia: teleconsultation using mobile devices.

Background: Sexual risk behaviors associated with poor information on sexuality have contributed to major public health problems in the area of sexual and reproductive health in teenagers and young adults in Colombia.

Objective: To report our experience with the use of DoctorChat Mobile to provide sexual education and information among university students in Bogota, Colombia, and knowledge about the sexual risk factors detected among them.

Methods: A mobile app that allows patients to ask about sexual and reproductive health issues was developed.

RNA interference of Marlin-1/Jakmip1 results in abnormal morphogenesis and migration of cortical pyramidal neurons.

The formation of the nervous systems requires processes that coordinate proliferation, differentiation and migration of neuronal cells, which extend axons, generate dendritic branching and establish synaptic connections during development. The structural organization and dynamic remodeling of the cytoskeleton and its association to the secretory pathway are critical determinants of cell morphogenesis and migration. Marlin-1 (Jakmip1) is a microtubule-associated protein predominantly expressed in neurons and lymphoid cells.

[Cost-effectiveness of laparoscopic versus open cholecystectomy].

Introduction: Cholecystectomy has been the subject of several clinical and cost comparison studies.

Objective: The results of open or laparoscopy cholecystectomy were compared in terms of cost and effectiveness from the perspective of health care institutions and from that of the patients.

Materials And Methods: The cost-effectiveness study was undertaken at two university hospitals in Bogotá, Colombia.

Neuronal protein trafficking: emerging consequences of endoplasmic reticulum dynamics.

The highly polarized morphology and complex geometry of neurons is determined to a great extent by the structural and functional organization of the secretory pathway. It is intuitive to propose that the spatial arrangement of secretory organelles and their dynamic behavior impinge on protein trafficking and neuronal function, but these phenomena and their consequences are not well delineated. Here we analyze the architecture and motility of the archetypal endoplasmic reticulum (ER), and their relationship to the microtubule cytoskeleton and post-translational modifications of tubulin.

Web-based asynchronous teleconsulting for consumers in Colombia: a 2-year follow up.

Background: Remote consultation was implemented in 2006 in our institution, through an open-access Web-based Teleconsulting service: Doctor Chat. This tool was created with the aim of improving access to health care services in Colombia, especially in underserved areas.

Objective: The aim of this paper is to report our experience with the free Web-based application for teleconsultation.

[Health care workers' perception of the Internet and mobile technologies in Colombia].

In July 2007 in Medellín, Colombia, 1,200 health care professionals were asked to complete a questionnaire: of the 493 who participated, the mean age was 31.2 years; 58.8% were physicians; and 97.

Web-based asynchronous teleconsulting for consumers in Colombia: a case study.

Background: Fourteen years after the reform to Colombia's health system, the promises of universality, improved equity, efficiency, and better quality of care have not materialized. Remote areas remain underserved and access to care very limited. Recognizing teleconsultation as an effective way to improve access to health care and health information, a noncommercial open-access Web-based application for teleconsultation called Doctor Chat was developed.