Ariel Arias

Health Canada | HC · Department of Biological Sciences

Many of the mechanisms that control insulin processing and packaging by interaction with different elements along the secretory pathway remain poorly understood. We have investigated the possibility that Cpn60, a member of the heat shock protein family, may be present in rat insulin-secreting cells, participating in the proinsulin-insulin maturatio...

The biological significance and function of pancreatitis-associated protein (PAP), identified in 1984 as a new secretory protein appearing during pancreatitis, remain to be elucidated. The purpose of this study was to evaluate the presence of PAP in pancreatic tissue upon its exposure to chlorophenylalanine methyl ester (CPME), a drug known to disr...

In the present study we report the occurrence of chaperonins, cpn10 and cpn60, in Chromatium vinosum and rat hepatocytes, using specific polyclonal antibodies in conjunction with the protein A-gold immunocytochemical technique. As demonstrated by quantitative evaluations, the immunolabeling for cpn10 and cpn60 in C vinosum cells was associated prim...

Molecular chaperones have recently been shown to be accurately located along distinct cellular compartments of the secretory pathway of pancreatic acinar cells. Since the aberrant aggregation of secretory proteins leading to the formation of RER intracisternal crystals induced by DL-p-chlorophenylalanine methyl ester (CPME) comprises major changes...

Three chaperones, the chaperonins cpn10 and cpn60, and the hsp70 protein, were revealed by immunochemistry and cytochemistry in pancreatic rat acinar cells. Western immunoblotting analysis of rat pancreas homogenates has shown that antibodies against cpn10, cpn60 and hsp70 protein recognize single protein bands of 25 kDa, 60 kDa and 70 kDa, respect...

Mechanisms leading to the formation of crystalline inclusions in the cisternal space of the rough endoplasmic reticulum are poorly understood. This phenomenon was investigated in pancreatic acinar cells using two different experimental models: 1) Intraperitoneal injection of DL-p-chlorophenylalanine methyl ester, and 2) culture of isolated acinar c...

Previous studies have shown that a combination of both the extracellular matrix and secretagogues plays critical roles in the maintenance of well-differentiated pancreatic acinar cells in culture. In the present study, we have shown that, upon proper stimulation, acinar cells change their growth pattern and morphologic appearance to a duct like phe...

To establish the significance of the addition of trypsin inhibitors to pancreatic acinar cells maintained in vitro, cells were cultured in the presence or absence of soybean trypsin inhibitor. Both cultures exhibited similar growth pattern, ultrastructural appearance, as well as secretory properties. Moreover, there was no evidence of trypsinogen a...

The effect of two different types of secretagogues on rat pancreatic acinar cells cultured onto a reconstituted basement membrane was studied. Cells cultured without any secretagogue were able to reaggregate but did not form monolayer patches. Most of them lost their differentiated ultrastructural characteristics but regained their polarity. In con...

This report describes 11 cases of Plasmodium vivax infection of Colombian origin that relapsed 49-166 days following treatment with chloroquine or amodiquine (1.5 g in 3 days) plus primaquine (15 mg daily for 14 days) a regimen widely used to effect radical cure of infections with this parasite. Relapses occurred under conditions that precluded rei...

Levels of superoxide dismutase (SOD) activity and its properties in Plasmodium falciparum-infected erythrocytes, isolated parasites, and noninfected erythrocytes were studied. A higher specific activity was found in P. falciparum-infected erythrocytes compared to noninfected erythrocytes, resulting from the lower protein content of infected cells a...

Sensitivity of Plasmodium falciparum to several antimalarial drugs was determined by in vitro and in vivo tests. Chloroquine resistance in vitro was detected in 97 of 101 patients from different geographic areas of Colombia. Sensitivity to amodiaquine in vitro was observed in 29 of 30 P. falciparum isolates. In vitro sensitivity to amodiaquine was...

Se describen 3 casos de malaria en niños incluyendo el diagnóstico y tratamiento, la evolución y las complicaciones. El primer caso corresponde a una lactante menor con un avanzado estado de desnutrición y una infección post-transfusional por Plasmodium vivax. La respuesta a la cloroquina no fue adecuada requiriendo 2 ciclos adicionales para elimin...

Se describe el primer informe de un caso confirmado del síndrome de esplenomegalia tropical (S.E.T.) en Colombia en una paciente de 9 años residente en la Serranía de la Macarena, Departamento del Meta, zona endémica para malaria. La paciente tenía antecedentes de infecciones a repetición por P. vivax, esplenomegalia de 10 cm., anemia, crioglubulin...

Se estudiaron 169 pacientes hospitalizados en el lnstituto Materno Infantil de Bogotá con diagnóstico clínico de Candidosis, practicándose examen microscópico directo de sus lesiones con cultivo subsecuente para intentar aislar al microorganismo responsable. Se obtuvieron 137 aislamientos, de los cuales el 89.7% correspondieron a Candida albicans y...