Marcela Camacho

Marcela Camacho
National University of Colombia | UNAL · Departamento de Biología (Bogotá)

About

46
Publications
6,000
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
284
Citations

Publications

Publications (46)
Article
The analysis of cell motion in an acoustic field is of interest as it can lead to new methods of cell separation, isolation and manipulation for diagnosis and treatment of diseases. Studies of the motion of different species of Leishmania parasites during exposure to ultrasonic standing waves in a microfluidic device allowed identification of acous...
Article
Particles or cells in suspension and exposed to ultrasonic waves experience an acoustic radiation force (FR) which, under certain conditions, drives them toward positions of acoustic equilibrium. In this paper, we present a three-dimensional model of the particle motions within the acoustic field generated by ultrasonic standing waves. This model a...
Poster
Full-text available
Outer membrane vesicles (OMV) have been proposed as exogenous antigen carriers. In order to discriminate effects associated with antigen specificity from those derived from OMV alone, the impact of their internalization on the electrical properties of macrophages was determined. The model studied was the murine macrophage-like cell line J774.A1 exp...
Poster
Full-text available
CLASSICAL ACTIVATION OF MACROPHAGE LIKE CELL LINE J774A.1 DURING THE INTERNALIZATION OF OMV FROM E. coli JC8031
Research
Electrophysiological caracgterization of leishmania amazonensis infected macrophages J774.A1
Article
Full-text available
Split-flow fractionation (SPLITT) is a family of techniques that separates in the absence of labeling using very low flow rates and force fields, and is therefore expected to minimize cell damage. Although it has been documented that separation methods cause physiological changes in immune cells that are attributable to mechanical stress and antibo...
Article
Full-text available
La resistencia a antimicrobianos representa un aspecto natural de evolución bacteriana, que puede resultar de mutaciones o por adquisición de genes foráneos. Hay diferentes posturas sobre el origen de ésta resistencia que explican la habilidad de estos microorganismos de adquirir nuevas características. Las teorías de la evolución de Lamarck y Darw...
Thesis
Full-text available
Despite the significant morbidity and mortality of infectious-contagious diseases nowadays, the alternatives for treatment and immunization are not satisfactory. For this reason, the search for new control strategies for this group of pathologies becomes imperative. In this context, controlled release technologies such as outer membrane vesicles (O...
Conference Paper
Full-text available
In order to evaluate the physiological impact of outer membrane vesicles (OMV) obtained from E. coli JC8031, as exogenous antigen carriers, we studied the effect of the internalization of “empty” OMV (without exogenous antigens) on the electrophysiological properties of the macrophage-like cell line J774A.1 Whole cell patch-clamp recordings were us...
Poster
Full-text available
Outer membrane vesicles (OMV) have been proposed as exogenous antigen carriers. In order to discriminate effects associated with antigen specificity from those derived from OMV alone, the impact of their internalization on the electrical properties of macrophages was determined. The model studied was the murine macrophage‐like cell line J774.A1 exp...
Article
Full-text available
The uses of ultrasounds in medical applications like ultrasonic surgery, diagnosis, and nowadays in cellular separations and manipulations, has foment the study about physical and biological effects, related to exposure of cells at an acoustic field. The interest in determining these effects could help to optimize the ultrasound uses, and identify...
Article
Full-text available
p>Leishmania es un protozoario patógeno, que transita durante su ciclo de vida desde el intestino de su vector hasta un compartimiento fagolisosomal al interior de su célula hospedera, el macrófago. Durante este recorrido el parásito está expuesto a ambientes que cambian en temperatura, pH y presumiblemente osmolaridad. Para su supervivencia, Leish...
Article
Though blood bank processing traditionally employs centrifugation, new separation techniques may be appealing for large scale processes. Split-flow fractionation (SPLITT) is a family of techniques that separates in absence of labelling and uses very low flow rates and force fields, and is therefore expected to minimize cell damage. However, the hyd...
Article
Leishmania is a protozoan pathogen that transits during its lifecycle from the gut of the vector to a phagolysosomal compartment within its host cell, the macrophage. During this journey, the parasite is exposed to environments that change in temperature, pH and osmolarity. For their survival, Leishmania must make adjustments to adapt and expressio...
Research
Full-text available
Betancourt, A., Maldonado, A., Maldonado, R., Camargo, A., Guzmán, A., Annicchiarico, I., Arroyave, J., Malagón, N., Pardo, L., Pérez, H., Ruiz, A., Eljach, L. & Camacho, M. (2002). Efectos de la inversión de la imagen en el reconocimiento de rostros [Image inversion effect on face recognition]. Acta Biológica Colombiana, 7, 53-57.
Poster
Full-text available
Leishmaniasis is a re-emerging tropical disease caused by parasitic protozoa of the genus Leishmania. The life cycle of this pathogen includes a mosquito vector and a vertebrate. After entry into its mammalian host, the parasite is taken up by cells of the immune system, macrophages, and confined into a low pH intra-cellular compartment known as th...
Article
Full-text available
Some intracellular parasites inhabit intracellular compartments known as parasitophorous vacuoles. To maintain and amplify infection, infective forms of the parasite must exit from the host cell to infect new cells. During parasite egress, two main mechanisms have been proposed: lysis of the membranes of the parasitophorus vacuole and the plasma me...
Article
Full-text available
Algunos parásitos intracelulares durante la infección en hospederos vertebrados se localizan al interior de sus células hospederas en un compartimiento intracelular rodeado por membrana denominado vacuola parasitófora. Para el sostenimiento e incremento de las infecciones causadas por estos parásitos es necesario que se dé un evento de liberación/s...
Article
Full-text available
Understanding the impact of intracellular pathogens on the behavior of their host cells is key to designing new interventions. We are interested in how Leishmania alters the electrical function of the plasma membrane of the macrophage it infects. The specific question addressed here is the impact of Leishmania infection on macrophage membrane prope...
Article
After a primary infection protocol of macrophages with Leishmania amazonensis, the percentage of infection drops as infection progresses and the uninfected population of macrophages mask the effects of infection for electrophysiological studies. In order to increase or maintain the infection percentage, we introduce an enrichment process after prim...
Article
We studied macroscopic ion currents from macrophages and compared their patterns of behavior using classical and fractal analysis. Peak and steady state currents were measured respectively at the beginning and end of a voltage-clamp pulse. Hurst coefficients H and fractional dimensions were calculated for the current fluctuations (I H ) during the...
Article
Full-text available
Understanding the impact of intracellular pathogens on the behaviour of their host cells is key to designing new interventions. We are interested in how Leishmania alters the electrical functioning of the plasma membrane of the macrophage it infects. The specific question addressed here is whether Leishmania amazonensis infection alters the macroph...
Article
Transport mechanisms involved in pH homeostasis are relevant for the survival of Leishmania parasites. The presence of chloride conductive pathways in Leishmania has been anticipated since anion channel inhibitors limit the proton extrusion mediated by the H+ATPase, which is the major regulator of intracellular pH in amastigotes. In this study, we...
Article
Full-text available
Leishmania are intracellular parasites of macrophages, confined into compartments known as parasitophorous vacuoles. The permeability of this compartment depends on its interaction with the endocytic pathway and transport proteins present on its membrane. The membrane permeability of the parasitophorous vacuole was studied in J774.A1-macrophage lik...
Article
Full-text available
Introducción. Leishmania son parásitos intracelulares de macrófagos, confinados encompartimentos denominados vacuolas parasitóforas. La permeabilidad de este compartimentodepende de su interacción con el tráfico vesicular y transportadores presentes en su membrana. Objetivo. En este trabajo se estudió la permeabilidad de la membrana de la vacuola...
Article
Full-text available
We compared the in vitro growth of promastigotes from two Leishmania species in TC-100 and Schneider media. Leishmania (Leishmania) amazonensis replication rates were similar in both tissue culture media and reached maximum rates by 48 h. In contrast Leishmania (Viannia) braziliensis growth was significantly greater in TC-100 but maximum rates were...
Article
La expresión heteróloga de canales iónicos en la membrana de los ovocitos de anfibio es una herramienta muy útil para la caracterización de dichos canales.
Article
Full-text available
Oocytes from Xenopus laevis are commonly used as an expression system for ion channel proteins. The aim of this study was to determine whether oocytes from the Colombian native toad, Bufo marinus, could be used as an alternative expression system for ion channel protein expression and functional characterization using the two-microelectrode voltage...
Article
Full-text available
La expresión en sistemas heterólogos ha sido una herramienta ampliamente utilizada enlos últimos años para el estudio funcional y estructural de proteínas. Para la carac-terización de las propiedades biofísicas de canales, bombas y transportadores engeneral su expresión en ovocitos de Xenopus laevis, ha sido fundamental. Este estudioreporta la expr...
Article
Full-text available
Whole cell patch-clamp recordings were used to study the electrical properties of the macrophage-like cell line J774.1, after infection with Leishmania amazonensis. Infection induced a significant increase in cell size and membrane capacitance, suggesting that parasite invasion leads to the addition of plasma membrane to the host cell. By 24 hr aft...
Article
The Na/K-pump or Na+/K(+)-ATPase (EC 3.6.1.37), couples the hydrolysis of ATP to the active transport of Na+ and K+ ions across the plasma membrane of virtually all animal cells. The relationship between activity of the Na+/K(+)-ATPase and the sensitivity of Schistosoma mansoni to immunological attack has been investigated. It has been observed tha...
Article
Full-text available
Acetylcholinesterase (AChE) is present in the muscle and on the tegument of schistosomes. Molecular forms of schistosome AChE were examined because particular AChEs are found in tissues of distinct function elsewhere. The dimeric globular form (G2) is the only form evident in adult Schistosoma haematobium: 32% of the muscle AChE is hydrophilic and...
Article
The blood dwelling stages of schistosomes have acetylcholinesterase (AChE) and nicotinic-like acetylcholine receptors (nAChR) on their teguments. Both AChE and nAChR are concentrated on the dorsal surface of the adult male, a major surface for nutrient uptake for the worm pair. Exposure of tegumental AChE and nAChR to acetylcholine (ACh), the natur...
Article
A simple flow culture apparatus was designed for the short-term in vitro culture of adult schistosomes. The use of this system allowed sensitive estimation of relative rates of glucose uptake by different species of schistosome. These data suggest that in parasites maintained carefully in conditions within the physiological range of glucose concent...
Article
Blood dwelling stages of schistosomes have acetylcholinesterase (AChE) on their teguments. As an initial step towards understanding the function of tegumental AChE, we have used specific ligand-binding assays to identify nicotinic acetylcholine receptors (nAChR) on the schistosome surface. AChR could not be detected on migratory stages using fluoro...
Article
Acetylcholinesterase (AChE) is present in all stages of the life-cycle of schistosomes and is located in muscle and on the surface of the parasite. Metrifonate is a drug that inhibits AChE. We compared the AChEs from three schistosome species (Schistosoma mansoni, Schistosoma haematobium and Schistosoma bovis) that have different susceptibilities t...
Article
Full-text available
Recibido 22 de Oct. 2007; Aceptado 16 de Jun. 2008; Publicado en línea 25 de Jul. 2008 Resumen El canal Gramicidina A es el más estudiado tanto teórica como experimentalmente. En la literatura hay abundantes trabajos sobre el potencial de fuerza media (P F M) que un catión experimenta cuando pasa a través del canal. A pesar dé esto, no ha sido posi...

Network

Cited By

Projects

Projects (3)
Archived project
Charaterization of the electrophysiological properties oof potassium channels of macrophages J774.A1 during apoptotic proces
Archived project
Electrophysiological characterization of leishmania amazonensis infected macrophages J744.A1
Project
En este estudio proponemos caracterizar la permeabilidad iónica (actividad de los canales iónicos) de la membrana plasmática de macrófagos murinos (Línea celular J774.A1) y la expresión de marcadores moleculares de activación celular, durante la internalización de OMV (OMV "vacías" y OMV cargadas con antígenos de Leishmania sp.) de una cepa no-patógena de E. coli JC8031 [6]. La aproximación metodológica para el estudio funcional de la interacción macrófago-OMV de E. coli JC8031 que aquí se propone, comprende el uso de técnicas de bioquímica, inmunología, ingeniería genética y electrofisiología. Nuestra propuesta de estudio permitirá generar nuevo conocimiento para aplicarlo al desarrollo de estrategias terapéuticas (vacunas) con OMV.