The glycosomal-membrane associated phosphoglycerate kinase isoenzyme A plays a role in sustaining the glucose flux in Trypanosoma cruzi epimastigotes.

In Trypanosoma cruzi three isoenzymes of phosphoglycerate kinase (PGK) are found which are simultaneously expressed: the cytosolic isoenzyme PGKB as well as two glycosomal enzymes, PGKA and PGKC. In this paper, we show that PGKA in T. cruzi epimastigotes is associated to the glycosomal membrane; it is responsible for about 23% of the glycosomal PGK activity, the fraction that remains in the pellet after osmotic shock treatment of purified organelles, in contrast to the 77% soluble activity that is mainly attributed to PGKC. Antibodies against the unique 80 amino-acid insertion of PGKA blocked almost completely the glucose consumption by epimastigotes that were partially permeabilized with digitonin. These results indicate that PGKA is the predominant isoenzyme for sustaining glycolysis through the glycosomes of these parasites.

[Economic factors related to the Millennium Development Goals: a literature review]. / Factores económicos relacionados con los Objetivos de Desarrollo del Milenio en salud: una revisión bibliográfica.

OBJECTIVES: To systematize all the information published on the status of and progress made toward the Health-related Millennium Development Goals (HMDGs), as well as to understand associations with certain economic factors and the potential for success. METHODS: A search was conducted for all scientific articles covering the Millennium Development Goals in general, published from 1 January 2000 to 31 August 2006, in the electronic databases of the EBSCO, CSA Illumina, Thomson Gale, SwetsWise, and BIREME. All original articles in English or Spanish that evaluated HMDG status, progress, and determinants were selected. The analysis evaluated the distribution of determinants of HMDG status or progress, the HMDGs referred to, the study type, the relationship between economic indicators and health, the study location, and the status and potential for attaining the HMDGs. The quality of the articles was also rated. RESULTS: Of the 304 original articles found, 114 (37.5%) covered one or more HMDGs. The most frequently addressed goals were those concerning infant and maternal mortality. Of the 39 articles that evaluated HMDGs and their association with economic variables, 13 dealt with economic factors related to equity, policy, or globalization. Economic and policy factors were most frequently associated with HMDG status or progress. CONCLUSIONS: There is a definitive trend toward measuring HMDG status and progress according to economic factors that reflect the population's condition. There is an information gap regarding government spending, international commerce, international aid, and global economic policy. The potential for achieving HMDGs in poor countries is low.

Factores económicos relacionados con los Objetivos de Desarrollo del Milenio en salud: una revisión bibliográfica / Economic factors related to the Millennium Development Goals: a literature review

OBJETIVOS: Sistematizar la información publicada sobre la situación y los avances en el logro de los Objetivos de Desarrollo del Milenio relacionados con la salud (ODMS), así como analizar su asociación con algunos factores económicos y los pronósticos de cumplimiento. MÉTODOS: Se realizó una búsqueda de los artículos científicos sobre los Objetivos de Desarrollo del Milenio en general publicados entre el 1 de enero de 2000 y el 31 de agosto de 2006 en las bases bibliográficas electrónicas EBSCO, CSA Illumina, Thomson Gale, SwetsWise y BIREME. Se seleccionaron los artículos originales en inglés o español que evaluaran la situación de los ODMS o sus avances y se refirieran a factores determinantes. Se analizó la distribución de los factores determinantes de la situación de los ODMS o sus avances, los ODMS referidos, el tipo de evaluación, la relación entre los indicadores económicos y la salud, el lugar estudiado, y la situación y los pronósticos del cumplimiento de los ODMS. Se valoró la calidad de los artículos. RESULTADOS: Se identificaron 304 artículos originales, de ellos 114 (37,5 por ciento) se ocupaban de uno o varios ODMS. Los objetivos relacionados con la mortalidad infantil y materna fueron los más frecuentemente abordados. De los 39 artículos que evaluaban los ODMS y su relación con los factores económicos, en 13 se consideraban factores económicos relacionados con la equidad, la política o la globalización. Los factores económicos y políticos fueron los más frecuentemente asociados con la situación de los ODMS o sus avances. CONCLUSIONES: Existe una tendencia a utilizar variables económicas vinculadas con las condiciones de la población para analizar la situación de los ODMS y sus avances. Falta información sobre la relación con el gasto gubernamental, el comercio exterior, la ayuda externa y las políticas económicas mundiales. Los pronósticos para lograr los ODMS en los países pobres son desfavorables.

OBJECTIVES: To systematize all the information published on the status of and progress made toward the Health-related Millennium Development Goals (HMDGs), as well as to understand associations with certain economic factors and the potential for success. METHODS: A search was conducted for all scientific articles covering the Millennium Development Goals in general, published from 1 January 2000 to 31 August 2006, in the electronic databases of the EBSCO, CSA Illumina, Thomson Gale, SwetsWise, and BIREME. All original articles in English or Spanish that evaluated HMDG status, progress, and determinants were selected. The analysis evaluated the distribution of determinants of HMDG status or progress, the HMDGs referred to, the study type, the relationship between economic indicators and health, the study location, and the status and potential for attaining the HMDGs. The quality of the articles was also rated. RESULTS: Of the 304 original articles found, 114 (37.5 percent) covered one or more HMDGs. The most frequently addressed goals were those concerning infant and maternal mortality. Of the 39 articles that evaluated HMDGs and their association with economic variables, 13 dealt with economic factors related to equity, policy, or globalization. Economic and policy factors were most frequently associated with HMDG status or progress. CONCLUSIONS: There is a definitive trend toward measuring HMDG status and progress according to economic factors that reflect the population's condition. There is an information gap regarding government spending, international commerce, international aid, and global economic policy. The potential for achieving HMDGs in poor countries is low.

Policy determinants affecting the hunger millennium development goal.

The possible effect of Government Consumption (a component of Gross Domestic Product (GDP)) on attainment of the hunger Millennium Development Goal (MDG1) was analyzed by evaluating the effect of macroeconomic, social, demographic and policy variables on average undernourished population. Eighty-four developing countries with data available on undernourished population were included in an ecological study. Regression models were applied to explore possible determinants of Undernourished between 1990 and 2004 and consequent achievement of the projected 2004 MDG1. In 2004, 1.4% of the overall undernourished population in the studied countries [70.16 million people] was in excess of the projected level required to meet MDG1. The multiple linear regression showed significant associations between Undernourished and poverty levels, the Gini Index, rural population and Government Consumption. The multiple logistic regression showed significant associations between achievement of projected 2004 MDG1 levels and Government Consumption and the Gini Index. The significant associations between Undernourished and Government Consumption suggest that the effects of GDP components on social conditions call for more thorough research and that policymakers such as governments and international financial institutions need to ensure that changes in distributive and redistributive policies do not negatively affect the possibility of achieving MDG1.

High throughput virus-induced gene silencing implicates heat shock protein 90 in plant disease resistance.

Virus-induced gene silencing was used to assess the function of random Nicotiana benthamiana cDNAs in disease resistance. Out of 4992 cDNAs tested from a normalized library, there were 79 that suppressed a hypersensitive response (HR) associated with Pto-mediated resistance against Pseudomonas syringae. However, only six of these clones blocked the Pto-mediated suppression of P.syringae growth. The three clones giving the strongest loss of Pto resistance had inserts corresponding to HSP90 and also caused loss of Rx-mediated resistance against potato virus X and N-mediated tobacco mosaic virus resistance. The role of HSP90 as a cofactor of disease resistance is associated with stabilization of Rx protein levels and could be accounted for in part by SGT1 and other cofactors of disease resistance acting as co-chaperones. This approach illustrates the potential benefits and limitations of RNA silencing in forward screens of gene function in plants.

Differential expression and function of Arabidopsis thaliana NHX Na+/H+ antiporters in the salt stress response.

The Arabidopsis thaliana vacuolar Na+/H+ antiporter AtNHX1 is a salt tolerance determinant. Predicted amino acid sequence similarity, protein topology and the presence of functional domains conserved in AtNHX1 and prototypical mammalian NHE Na+/H+ exchangers led to the identification of five additional AtNHX genes (AtNHX2-6). The AtNHX1 and AtNHX2 mRNAs are the most prevalent transcripts among this family of genes in seedling shoots and roots. A lower-abundance AtNHX5 mRNA is present in both shoots and roots, whereas AtNHX3 transcript is expressed predominantly in roots. AtNHX4 and AtNHX6 mRNAs were detected only by RT-PCR. AtNHX1, 2 or 5 suppress, with differential efficacy, the Na+/Li+-sensitive phenotype of a yeast mutant that is deficient in the endosomal/vacuolar Na+/H+ antiporter ScNHX1. Ion accumulation data indicate that these AtNHX proteins function to facilitate Na+ ion compartmentalization and maintain intracellular K+ status. Seedling steady-state mRNA levels of AtNHX1 and AtNHX2 increase similarly after treatment with NaCl, an equi-osmolar concentration of sorbitol, or ABA, whereas AtNHX5 transcript abundance increases only in response to salt treatment. Hyper-osmotic up-regulation of AtNHX1, 2 or 5 expression is not dependent on the SOS pathway that controls ion homeostasis. However, steady-state AtNHX1, 2 and 5 transcript abundance is greater in sos1, sos2 and sos3 plants growing in medium that is not supplemented with sorbitol or NaCl, providing evidence that transcription of these genes is negatively affected by the SOS pathway in the absence of stress. AtNHX1 and AtNHX2 transcripts accumulate in response to ABA but not to NaCl in the aba2-1, mutant indicating that the osmotic responsiveness of these genes is ABA-dependent. An as yet undefined stress signal pathway that is ABA- and SOS-independent apparently controls transcriptional up-regulation of AtNHX5 expression by hyper-saline shock. Similar to AtNHX1, AtNHX2 is localized to the tonoplast of plant cells. Together, these results implicate AtNHX2 and 5, together with AtNHX1, as salt tolerance determinants, and indicate that AtNHX2 has a major function in vacuolar compartmentalization of Na+.