La identidad 'clase obrera' a revisión: una lectura de las representaciones del Congreso Obrero de Ambato de 1938 (Estudios)

1. El Congreso Obrero de Ambato; 2. Representaciones de las clases trabajadoras; 3. Artesanos versus obreros fabriles: o la 'lucha entre la clases'; 4. Mujer y clase obrera; 5. Indígenas y clase obrera; 6. Conclusiones

La Constitución ecuatoriana de 1861: el debate (Estudios)

El artículo analiza el proceso de elaboración de la Constitución ecuatoriana de 1861, sus principales innovaciones y los debates que suscitó. Esta carta constitucional amplió el sufragio y modificó la estructura administrativa territorial, y sustituyó la división geográfica del Ecuador en departamentos por provincias. También revisa los impactos regionales que produjo la nueva estructura administrativa. Además, el estudio realiza una descripción de la coyuntura en que ascendió Gabriel García Moreno a la jefatura del Estado ecuatoriano y las discrepancias en torno a las libertades individuales, las políticas económicas y las relaciones entre la Iglesia y el Estado católico.

Las relaciones diplomáticas entre García Moreno y la Santa Sede (1861-1866)

El presente texto busca dilucidar las tratativas diplomáticas entre García Moreno y la Santa Sede que ocurrieron entre el 1861 y 1866 y cuyo fin era conseguir el Concordato: un pacto que el Presidente ecuatoriano consideraba fundamental para la realización de su proyecto de reformas. Frente a un país lacerado por luchas internas y dividido entre sí, era necesario un cambio enérgico para establecer el orden social y la unión nacional. Paladino de la reforma debía ser, según García Moreno, el clero a su vez reformado y vuelto ejemplo de virtud para restituir el orden y la moral al país entero. Entonces, era primordial un Concordato con la Santa Sede para imponer la reforma del clero y establecer los límites entre poder religioso y estatal. No obstante el Concordato no representó una solución fácil e inmediata al cambio, en cuanto planteó una serie de contrastes, discusiones, reformulaciones y cambios que desvelaron los intereses que rodeaban al poder estatal y religioso en el país. En este contexto la Santa Sede iba a representar una fuente legitimadora del poder religioso, demostrando su preferencia en tratar las cuestiones con el Presidente ecuatoriano y su legítimo gobierno, marginando el parlamento. El Concordato resultó ser un documento que permitió a García Moreno fortalecer su control sobre la Iglesia ecuatoriana y mediar con la Santa Sede algunas cuestiones, sobre todo la inherente el diezmo, obteniendo una mayor ventaja económica para el Estado. Soluciones que, no fueron definitivas, sino que dejaron abierta la discusión para ulteriores tratativas.

Expression and regulation of 80K/MARCKS, a major substrate of protein kinase C, in the developing rat heart

Objective: Protein kinase C (PKC) plays a pivotal role in modulating the growth and differentiation of many cell types including the cardiac myocyte. However, little is known about molecules that act immediately downstream of PKC in the heart. In this study we have investigated the expression of 80K/MARCKS, a major PKC substrate, in whole ventricles and in cardiac myocytes from developing rat hearts. Methods: Poly A+ RNA was prepared from neonatal (2-day) and adult (42-day) cardiac myocytes and whole ventricular tissue and mRNA expression determined by reverse transcription-polymerase chain reaction (RT-PCR) using primers designed to identify a 420 bp fragment in the 80K/MARCKS gene. Protein extracts were prepared from either 2-day and 42-day cardiac myocytes or from whole ventricular tissue at 2, 5–11, 14, 17, 21, 28 and 42 days of age. Protein expression was determined by immunoblotting with an 80K/MARCKS antipeptide antibody and PKC activity was determined by measuring the amount of γ32P-ATP transferred to a specific peptide substrate. Results: RT-PCR analysis of 80K/MARCKS mRNA in neonatal (2-day) and adult (42-day) cardiac myocytes showed the expression of this gene in both cell types. Immunoblotting revealed maximum 80K/MARCKS protein expression in whole ventricular tissue at 5 days (a 75% increase above values at 2 days), followed by a transient decrease in expression during the 6–8-day period (61% of the protein expressed at 2 days for 8-day tissue) with levels returning to 5 day levels by 11 days of age. 80K/MARCKS protein was present in cardiac myocytes at 2 days of age whereas it was not detectable in adult cells. In addition, PKC activity levels increased to 160% of levels present at 2 days in 8-day-old ventricles with PKC activity levels returning to 5-day levels by 9 days of age. This was then followed by a steady decline in both 80K/MARCKS protein expression and PKC activity through to adulthood. Conclusions: Expression of the PKC substrate, 80K/MARCKS, in cardiac myocytes changes significantly during development and the transient loss of immunoreactive protein during the 6–8-day developmental period may reflect 80K/MARCKS phosphorylation and subsequent down-regulation as a result of the concomitant up-regulation of PKC activity at this time.

MARCKS functions as a novel growth/tumour suppressor in cells of melanocyte origin

Protein kinase C (PKC) plays a pivotal role in modulating the growth of melanocytic cells in culture. We have shown previously that a major physiological substrate of PKC, the 80 kDa myristoylated alanine-rich C-kinase substrate (MARCKS), can be phosphorylated in quiescent, non-tumorigenic melanocytes exposed transiently to a biologically active phorbol ester, but cannot be phosphorylated in phorbol ester-treated, syngeneic malignant melanoma cells. Despite its ubiquitous distribution, the function of MARCKS in cell growth and transformation remains to be demonstrated clearly. We report here that MARCKS mRNA and protein levels are down-regulated significantly in the spontaneously derived murine B16 melanoma cell line compared with syngeneic normal Mel-ab melanocytes. In contrast, the tumourigenic v-Ha-ras-transfonned melan-ocytic line, LTR Ras 2, showed a high basal level of MARCKS phosphorylation which was not enhanced by treatment of cells with phorbol ester. Furthermore, protein levels of MARCKS in LTR Ras 2 cells were similar to those expressed in Mel-ab melanocytes. However, in four out of six murine tumour cell lines investigated, levels of MARCKS protein were barely detectable. Transfection of B16 cells with a plasmid containing the MARCKS cDNA in the sense orientation produced two neomycin-resistant clones displaying reduced proliferative capacity and decreased anchorage-independent growth compared with control cells. In contrast, transfection with the antisense MARCKS construct produced many colonies which displayed enhanced growth and transforming potential compared with control cells. Thus, MARCKS appears to act as a novel growth suppressor in the spontaneous transformation of cells of melanocyte origin and may play a more general role in the tumour progression of other carcinomas.

The role of 80K/MARCKS, a specific substrate of protein kinase C, in cell growth and tumour progression

Since its discovery more than a decade ago [Wu et al., 1982; Rozengurt et al., 1983], the 80-87 kDa myristoylated a lanine-rich C-kinase substrate (80K/MARCKS) protein has attracted a great deal of attention from researchers interested in cell growth and tumour progression. However, despite its ubiquitous distribution, a definitive functional role for 80K/MARCKS has not been found. The purpose of this review is to describe the properties, distribution and regulation of 80K/MARCKS and to discuss some of the most recent findings, both from our laboratory and from others, that have suggested a functional role for this protein in modulating cell growth and tumour progression. Furthermore, I will present data from our laboratory that implicates 80K/MARCKS as a novel tumour suppressor in cells of melanocyte origin.

Evolução administrativa da pesquisa agropecuaria no ambito do Ministerio da Agricultura no periodo de 1938/1978 : um estudo de caso

Nesta monografia buscou-se, através de um estudo de caso, analisar, basicamente, a evolução administrativa e a sobrevivência da pesquisa e experimentação agropecuárias,cujas ações estão diretamente ligadas ao Ministério da Agricultura. Envolve o período de 1938 a 1978, no qual a atividade científica foi desem penhada com o objetivo de gerar e adaptar tecnologias que, sob determinadas condições, pudessem contribuir para elevar os índices de produtividade e bem estar social do setor agrícola. Adotou-se como modelo de análise aquele proposto por Esman e B1aise e que na literatura especializada aparece sob a denominação de Institution Building. A partir da análise desenvolvida foi possível identificar algumas fases que se caracterizavam por diferentes níveis de desempenho organizacional. As conclusões a que o presente estudo permite chegar são limitadas, mas a sua contribuição reside no estímulo a esforços posteriores de pesquisa, cuja necessidade pode ser identificada a partir deste trabalho.