La estrategia de manufactura (EM) consiste en un plan a largo plazo para el sistema de producción/operaciones diseñado para apoyar la estrategia corporativa de la compañía. El contenido de la EM aborda las metas y las decisiones estratégicas necesarias para enfrentar la competencia. A pesar del creciente número de publicaciones sobre este tema, pocas investigaciones han sido realizadas en el contexto colombiano. Por tanto, el presente artículo expone los resultados de un estudio realizado en 36 empresas colombianas que aborda los tres componentes principales del contenido de la EM: las prioridades competitivas, las áreas estratégicas de decisión y los enfoques de gestión para la manufactura. Los resultados permitieron detectar dos grupos de empresas que exponen diferentes niveles de desempeño así como las relaciones de dicho resultado con las áreas de decisión estratégicas y los enfoques de gestión de manufactura.

Manufacturing strategy (MS) is a long-term plan for production and operations system aimed to support the company's corporate strategy. The content of MS addresses the goals and strategic decisions to face competition. Despite the number of contributions on this subject, few studies have been conducted in the Colombian context. Therefore, this article shows the results of a study undertaken in 36 Colombian companies addressing the three main components of the MS content: competitive priorities, strategic decision areas and the management's approach to manufacturing. The results allow two groups of companies with different performance level to be identified, as well as the relationship of this performance with strategic decision areas and the management's approach to manufacturing.

Introducción. Varios estudios in vitro sugieren que la proliferación, migración y supervivencia en líneas celulares de cáncer de seno se ven significativamente afectadas por la activación del receptor IGF de tipo I (Insulin-like GrowthFactor-I Receptor, IGF-IR). Objetivo. Caracterizar la fosforilación del IGF-IR y las moléculas de señalización intracelular Akt y Erk1/2 (vías de señalización PI-3K y MAPK, respectivamente), causada por el factor IGF-I en una línea celular colombiana de cáncer de mama ductal infiltrante (CSC 1595). Materiales y métodos. Las líneas celulares CSC 1595 y MCF-7 se cultivaron en medio DMEM con suplemento de suero fetal bovino 10%, glutamina 2 mM, penicilina 100 U/ml, estreptomicina 100 µg/ml a 37 0C, atmósfera de CO2 al 5% y humedad de 95%. Los extractos celulares se sometieron a inmunoprecipitación e inmunodetección con anticuerpos específicos anti-pIGF-IR, anti-pERK1/2 y anti-pAkt. Resultados. Cinco minutos después del estímulo con 10 nM de IGF-I, 70% y 25% del IGF-IR fueron fosforilados en las células CSC 1595 y MCF-7, respectivamente; también se observó activación de las proteínas Akt y ERK1/2. Los niveles basales y estimulados de las proteínas ERK1/2 fueron significativamente más altos en las células CSC 1595, comparados a los observados en MCF-7. Conclusiones. El IGF-IR y la vía MAPK cinasa que involucra las proteínas ERK1/2 muestran una fosforilación mayor en las células 1595 a la observada en las MCF-7. El IGF-IR, principal activador de esta vía, podría jugar un papel importante en los procesos de proliferación y metástasis de tumores de cáncer de mama ductal infiltrante.

Introduction. In vitro studies strongly suggest that proliferation, migration and cell survival of breast cancer cell lines are significantly affected by activation of the IGF type 1 receptor (IGF-IR). Objective. The phosphorylation by IGF-I of IGF-IR and the intracellular signaling molecules Akt (PI-3K pathway) and Erk1/2 (MAPK pathway) was characterized in a human breast cancer cell lines. Materials and methods. The study compared a standard breast adenocarcinoma line (MCF-7) cell line with a line (CSC 1595) derived from an infiltrating ductal breast cancer in a Colombian patient. The CSC 1595 and MCF-7 cell lines were cultured in DMEM supplemented with 10% fetal bovine serum, 2 mM glutamine, 100 U/ml penicillin, and 100 µg/ml streptomycin and grown at 37°C in 5% CO2 atmosphere and 95% humidity. Cell extracts were prepared, followed by immunoprecipitation and immunoblotting with specific anti-pIGF-IR, anti-pERK1/2 and anti-pAkt antibodies. Results. After 5 minute stimulation with IGF-I, 70% of the IGF-IR was phosphorylated in the cell line CSC 1595 and 25% in MCF-7. In addition, Akt (oncogene protein v-akt) and ERK1/2 (extracellular signal-regulated MAP kinases) were phosphorylated. Basal and stimulated levels of phosphorylated ERK1/2 were substantially higher compared to those in the MCF-7 cell line. Conclusions. The IGF-IR and MAPK kinase pathway involving proteins ERK1/2 showed more significant phosphorylation in the 1,595 cells compared to the observed in the MCF-7 cell line. Since the IGF-IR is the major activator of this pathway it may play an important role in ductal infiltrating breast cancer tumor growth and metastases.

A atividade citotóxica de extratos frações e subfrações obtidas das folhas e cascas de Bursera tomentosa (Jacq.) Triana & Planch., Burseraceae, foram preliminarmente avaliados pelo método MTT frente a linhagens celulares tumorais CSC-1595 e Colo 205. Os resultados mostraram que a subfração diclorometano-metanol (9.5:0.5), obtidos a partir da fração acetato de etila do extrato em éter de petróleo das folhas, como sendo a que apresenta substâncias bioativas com forte atividade citotóxica, taxa de viabilidade de 3% e de 15,3% na concentração de 30 µg/mL em linhagens de células tumorais humanas Colo 205 e CSC-1595, respectivamente.

To the extracts, fractions and subfractions obtained from leaves, flowers and bark of Bursera tomentosa (Jacq.) Triana & Planch., Burseraceae, its preliminary cytotoxic activity against to the cellular lines CSC-1595 and Colo 205 were evaluated, following the MTT method. The results showed that dichloromethane-methanol (9.5:0.5) subfraction obtained of ethyl acetate part from petroleum extract of leaves, like to display the bioactives substances with a strong cytotoxic activity, showing viability percentage of 3% and 15,3% to the concentration 30 µg/mL in human tumor cellular lines Colo 205 and CSC-1595 respectively.

A los extractos, fracciones y subfracciones obtenidos de hojas, flores y corteza de Bursera tomentosa (Jacq.) Triana & Planch., Burseraceae, se les evalúo su actividad citotóxica preliminar frente a las líneas celulares CSC-1595 y Colo 205, siguiendo el método de fraccionamiento guiado por bioensayo de citotoxicidad MTT. Los resultados obtenidos de esta prueba muestran a la subfracción en diclorometano-metanol (9.5:0.5) obtenida de la fracción acetato de etilo del extracto en éter de petróleo de hojas, como la que presentó las sustancias bioactivas con una marcada actividad citotóxica, con porcentajes de viabilidad del 3% y 15.3% a la concentración 30 µg/mL en las líneas tumorales humanas Colo 205 y CSC-1595 respectivamente.

O acetato de longipilina, o princípio ativo citotóxico, isolado de Espeletia killipii Cuatr., uma planta endêmica de Colômbia, é uma sesquiterpenlactona que tem a propriedade de induzir apoptose em algumas linhagens celulares de câncer de mama como MCF-7 e CSC-1595 (obtidas do Instituto Nacional de Cancerologia, Bogotá - Colômbia). Reconhecimento morfológico, método de Tunel e citometria de fluxo foram utilizados para avaliar a atividade apoptótica. Os resultados mostraram que a longipilina é um potencial agente antitumoral.

Longipilin acetate is the compound exhibiting cytotoxicity, isolated from endemic plant specie from Colombia, South America, Espeletia killipii Cuatr. Longipilin acetate is a sesquiterpenelactone having the ability to induce apoptosis in several breast cancer cell-lines like MCF-7 y CSC-1595 (obtained from National Cancer Institute, Bogotá Colombia), Morphological examination, nuclear DNA fragmentation, tunel and flow cytometry were used to evaluate apoptosis. Therefore longipilin acetate is a compound showing potential as an antitumor agent.

De Espeletia killipi Cuart. foi isolado uma sesquiterpenlactona identificada como acetato de longipilina que mostrou atividade citotóxica. A citotoxidade foi avaliada em células normais obtidas de sangue periférico, tiróide, testículo e epitélio da boca. Células da medula óssea de pacientes com leucemia crônica mielóide, linfoma de Hodking (do Instituto Nacional de Câncer de Bogotá, Colômbia) e células K562 também foram avaliadas. A citotoxidade foi determinada através do teste MTT (3-(4,5-dimethyldiazol-2-yl)-2,5 diphenyl Tetrazolium Bromid). Os ensaios mostraram que a substância não é tóxica para células normais mas a 3 mg/mL apresentou significante atividade em células tumorais e linhagem K562. Conseqüentemente, lavando-se em conta essa significante ação, novas investigações podem ser consideradas plausíveis.

The compound responsible for the citotoxic effect was identified as longipilin acetate, a sesquiterpenelactone isolated from Espeletia killipi Cuatr. Citotoxicity was assessed by using normal cells obtained from peripheral blood, thyroid, testicle and mouth epithelium. Bone marrow cells from patients with chronic myeloid leukemia, Hodking lymphoma (from Cancer National Institute, Bogotá Colombia) and the cell line K562 were also assayed. Citotoxicity was determined by the MTT cell viability test (3-(4,5-dimethyldiazol-2-yl)-2,5 diphenyl Tetrazolium Bromid]. The assays revealed that the substance is risk-free on normal cells but at 3 mg/mL has significant activity on tumor cells and K562 cell line. Consequently, taken into account this significant action, new research approaches can be foreseen.

O extrato etanólico e as frações de Espeletia killipii (espécie endêmica da vegetação dos páramos do altiplano Cundiboyacense); mostraram atividade citotóxica significativa in vitro nas linhagens celulares tumorais humanas de câncer de mama MCF-7, CSC-1170, CSC-1595, CSC-3322, CSC-3325 e na linhagem Hep-2 de laringe. A fração CH2Cl2 e suas sub-frações foram ativas contra as linhagens celulares cancerígenas de mama na concentração de 50 µg/mL, obtendo-se percentagens de viabilidade entre 13 e 20%. O principio ativo ainda não identificado foi obtido por ensaios bioguiados sucessivos e apresentou valores de Concentração Citotóxica media (CC50) menores que 1 µg/mL para as linhagens celulares colombianas CSC-1170, CSC-1595, CSC-3322 e CSC-3325; CC50 = 1 µg/mL contra MDA MB 435 e NCl-H23; contra MCF-7 uma CC50 = 2 µg/mL e uma CC50 superior a 16 µg/mL contra PC-3 e U-251.

It was found that the ethanol extracts and fractions of Espeletia killipii (an endemic species of the páramo vegetation of the Cundiboyacense plateau) exhibited cytotoxic activity against several human tumor cell lines. Thus, the extracts and fractions exhibited significant cytotoxic activity against both the human tumor cell lines of breast cancer MCF-7, CSC-1170, CSC-1595, CSC-3322, CSC-3325 and the Hep-2 cell lines of laryns. The CH2Cl2 fraction and its sub-fractions were active against the breast lines at concentration of 50 µg/mL, with a viability percentage between 13 and 20%. The active principle, not identified yet, was obtained by successive bio-directed assays. It showed activity against the Colombian cell lines CSC-1170, CSC-1595, CSC-3322 and CSC-3325 at a half Cytotoxic Concentration (CC50) less than 1 µg/mL, against MDA MB-435 and NCI-H23 at CC50= 1 µg/mL against MCF-7 at CC50= 2 µg/mL, and against PC-3 and U-251 at CC50 greater than 16 µg/mL.