Research capacity for institutional collaboration in implementation research on diseases of poverty.

OBJECTIVE: To assess the capacity for research collaboration and implementation research in strengthening networks and institutions in developing countries. METHODS: Bibliometric analysis of implementation research on diseases of poverty in developing countries from 2005 to 2010 through systematically searching bibliographic databases. Methods identified publication trends, participating institutions and countries and the cohesion and centrality of networks across diverse thematic clusters. RESULTS: Implementation research in this field showed a steadily growing trend of networking, although networks are loose and a few institutions show a high degree of centrality. The thematic clusters with greatest cohesion were for tuberculosis and malaria. CONCLUSIONS: The capacity to produce implementation research on diseases of poverty is still low, with the prominence of institutions from developed countries. Wide ranges of collaboration and capacity strengthening strategies have been identified which should be put into effect through increased investments.

Two types of MGDG synthase genes, found widely in both 16:3 and 18:3 plants, differentially mediate galactolipid syntheses in photosynthetic and nonphotosynthetic tissues in Arabidopsis thaliana.

In Arabidopsis, monogalactosyldiacylglycerol (MGDG) is synthesized by a multigenic family of MGDG synthases consisting of two types of enzymes differing in their N-terminal portion: type A (atMGD1) and type B (atMGD2 and atMGD3). The present paper compares type B isoforms with the enzymes of type A that are known to sit in the inner membrane of plastid envelope. The occurrence of types A and B in 16:3 and 18:3 plants shows that both types are not specialized isoforms for the prokaryotic and eukaryotic glycerolipid biosynthetic pathways. Type A atMGD1 gene is abundantly expressed in green tissues and along plant development and encodes the most active enzyme. Its mature polypeptide is immunodetected in the envelope of chloroplasts from Arabidopsis leaves after cleavage of its transit peptide. atMGD1 is therefore likely devoted to the massive production of MGDG required to expand the inner envelope membrane and build up the thylakoids network. Transient expression of green fluorescent protein fusions in Arabidopsis leaves and in vitro import experiments show that type B precursors are targeted to plastids, owing to a different mechanism. Noncanonical addressing peptides, whose processing could not be assessed, are involved in the targeting of type B precursors, possibly to the outer envelope membrane where they might contribute to membrane expansion. Expression of type B enzymes was higher in nongreen tissues, i.e., in inflorescence (atMGD2) and roots (atMGD3), where they conceivably influence the eukaryotic structure prominence in MGDG. In addition, their expression of type B enzymes is enhanced under phosphate deprivation.

Beyond health gain: the range of health system benefits expressed by social groups in Mexico and Central America.

Current health reform proposals in most developing countries stress health gain as the chief evaluation criterion. Essential service packages are formulated using cost-effectiveness methods for the selection of interventions without sufficient regard for other factors that are significant for successful implementation and acceptance by the needy. This paper presents the results of research undertaken in Mexico and Central America to test the hypothesis that population groups view health gain as only one among several benefits derived from health systems. The goal at this stage was two-fold: (a) to identify through qualitative methods the range of benefits that are significant for a wide cross-section of social groups and (b) to classify such benefits in types amenable to be used in the development of instruments to measure the benefits intended and actually produced by health systems. Fourteen focus groups were undertaken in Costa Rica, El Salvador, Guatemala, Mexico and Nicaragua representing diverse age, gender, occupation and social conditions. Six major types of health system benefits were identified besides health gain: reassurance/uncertainty reduction, economic security, confidence in health system quality, financial benefits derived from the system, health care process utility and health system fairness. Benefits most often mentioned can be classed under health care process utility and confidence in system quality. They also have the most consensus across social groups. Other benefits mentioned have an affinity with social conditions. Human resource-derived utility stands out by its frequency in the range of benefits mentioned. Health systems and health sector reform proposals must emphasise those aspects of quality related to human resources to be in accord with population expectations.

The multigenic family of monogalactosyl diacylglycerol synthases.

Because the synthesis of monogalactosyldiacylglycerol (MGDG) is unique to plants, identified as an important marker of the plastid envelope, involved in a key step of plastid biogenesis and is the most abundant lipid on earth, MGDG synthase activity was extensively analysed at the biochemical and physiological levels. In the present paper, we present our current knowledge on the MGDG synthase's function, structure and topology in envelope membranes, and discuss possible roles in plant cell glycerolipid metabolism. The recent discovery of a multigenic family of MGDG synthases raised the possibility that multiple isoenzymes might carry out MGDG synthesis in various tissues and developmental stages.

Biochemical and topological properties of type A MGDG synthase, a spinach chloroplast envelope enzyme catalyzing the synthesis of both prokaryotic and eukaryotic MGDG.

MGDG synthase, the enzyme that catalyzes the synthesis of the major chloroplast membrane lipid monogalactosyldiacylglycerol (MGDG), is encoded by a multigenic family. We have analyzed the biochemical properties, subcellular localization and membrane topology of a spinach chloroplast MGDG synthase, a representative member of the type A family from Spinacia oleracea (soMGD A), using a recombinant protein that was functionally overexpressed in Escherichia coli and specific polyclonal antibodies. We demonstrated that soMGD A could catalyze the synthesis of both 'prokaryotic' and 'eukaryotic' MGDG molecular species in vitro, with a selectivity for diacylglycerol similar to that of purified chloroplast envelope MGDG synthase activity. Furthermore, soMGD A was shown to be sensitive to chemical reagents (dithiothreitol, N-ethylmaleimide and o-phenanthroline) known to affect MGDG synthesis by the partially purified enzyme, as well as in isolated chloroplast envelope membranes. In spinach chloroplasts, soMGD A was localized by Western blot analysis in the inner envelope membrane. Topological studies demonstrated that soMGD A is a monotopic enzyme, embedded within one leaflet of the inner envelope membrane from spinach chloroplasts, a structure which may involve amphipathic alpha helices. We further demonstrated that in vitro, soMGD A precursor is imported and processed to its correct mature form in intact chloroplasts. These results show that soMGD A corresponds to a mature polypeptide of approximately 45 kDa. In addition, inactivation kinetics after gamma-ray irradiation strongly suggest that both native chloroplast envelope MGDG synthase and recombinant soMGD A have a functional molecular mass of 95-100 kDa, indicating that they are probably active as homodimers made of two 45-kDa subunits. This study suggests that, in spite of the growing evidence that MGDG synthesis is catalyzed by a multigenic family of enzymes, in spinach leaves both prokaryotic and eukaryotic MGDG syntheses could be attributable to a unique dimeric enzyme, provided that diacylglycerol is transported from the outer membrane to the inner membrane of the chloroplast envelope.

Do plastid envelope membranes play a role in the expression of the plastid genome?

A unique biochemical machinery is present within the two envelope membranes surrounding plastids (Joyard et al., Plant Physiol. 118 (1998) 715-723) that reflects the stage of development of the plastid and the specific metabolic requirements of the various tissues. Envelope membranes are the site for the synthesis and metabolism of specific lipids. They are also the site of transport of metabolites, proteins and information between plastids and surrounding cellular compartments. For instance, a complex machinery for the import of nuclear-encoded plastid proteins is rapidly being elucidated. The functional studies of plastid envelope membranes result in the characterization of an increasing number of envelope proteins with unexpected functions. For instance, recent experiments have demonstrated that envelope membranes bind specifically to plastid genetic systems, the nucleoids surrounded by plastid ribosomes. At early stages of plastid differentiation, the inner envelope membrane contains a unique protein (named PEND protein) that binds specifically to plastid DNA. This tight connection suggests that the PEND protein is at least involved in partitioning the plastid DNA to daughter plastids during division. The PEND protein can also provide a physical support for replication and transcription. In addition, factors involved in the control of plastid protein synthesis can become associated to envelope membranes. This was shown for a protein homologous to the E. coli ribosome recycling factor and for the stabilizing factors of some specific chloroplast mRNAs encoding thylakoid membrane proteins. In fact, the envelope membranes together with the plastid DNA are the two essential constituents of plastids that confer identity to plastids and their interactions are becoming uncovered through molecular as well as cytological studies. In this review, we will focus on these recent observations (which are consistent with the endosymbiotic origin of plastids) and we discuss possible roles for the plastid envelope in the expression of plastid genome.

Plant ribosome recycling factor homologue is a chloroplastic protein and is bactericidal in escherichia coli carrying temperature-sensitive ribosome recycling factor.

We have isolated a protein, mature RRFHCP, from chloroplasts of spinach (Spinacia oleracea L.) that shows 46% sequence identity and 66% sequence homology with ribosome recycling factor (RRF) of Escherichia coli. RRF recycles ribosomes through disassembly of the posttermination complex. From the cDNA analysis and from the amino-terminal sequencing of the isolated protein, the mature RRFHCP was deduced to have a Mr of 21,838 with 193 aa. It lacks the 78-aa chloroplast targeting sequence encoded by the RRFHCP cDNA sequence. The RRFHCP synthesized in vitro was imported into isolated chloroplasts with simultaneous conversion to the mature RRFHCP. Transcription of the gene coding for RRFHCP was not dependent on light, yet it was limited mostly to photosynthetic tissues in which only one transcript size was detected. Mature RRFHCP exerted a bactericidal effect on E. coli carrying temperature-sensitive RRF at the permissive temperature whereas wild-type E. coli was not affected.

Comparative research and analysis methods for shared learning from health system reforms.

The pace and breadth of health reforms point to the need for a comparative methodology to support shared learning from country experiences. A common understanding of health reforms is a first prerequisite for comparative research. Dimensions characterising content, sequence, process, purpose and scope of policy change are identified on the basis of a literature review. Reforms can have a gradual build up, starting with piecemeal policy changes that can be eventually integrated to enhance their benefits. Comprehensive reforms can be defined as policy formulation and implementation that comprises the systemic, programmatic, organisational and instrumental policy levels through explicit strategies sustained in well-documented experiences and theories and implemented with the support of a specialised agency with consensus-building capacity. A minimum-data set is proposed on the basis of an extensive literature review to support the comparability of health reform case studies and descriptions. Its components are: the current health system, its background and context, the reform rationale, the specific proposals, political actors and processes, achievements and limitations, and lastly the reform's wider impact. Case studies can be compared historically, through particularistic comparisons, using ideal types and by means of exemplars. The advantages and limitation of each method are analysed as well as how they can be combined to frame the research questions and minimise resources. Finally, the International Clearinghouse for Health System Reform Initiatives is described as an instrument to disseminate comparative research and analysis in support of shared learning.

[The decentralization of the Secretaría de Salud de México. The case of local health systems 1989-1994]. / La descentralización de la Secretaría de Salud de México. El caso de los sistemas locales de salud 1989-1994.

This article constitutes an analysis of the decentralization of the Ministry of Health of Mexico though the project to develop its jurisdictions to strengthen Local Health System (SILOS) implemented between 1989 and 1994. The relationship between decentralization and jurisdictional socioeconomic, demographic and resource availability differences was studied using qualitative and quantitative methods. The impact of jurisdictional strengthening on deconcentration and their combined effect on primary health care (PHC) and coverage were measured. The strengthening of technical capacity within the jurisdictions increased moderately but did not show a significant association with primary health care efficiency. However, when jurisdictions attain more autonomy, a significant association between strengthening and PHC efficiency appears. Deconcentration is a key factor to guarantee the strengthening of technical capacity and to assure that greater efficiency impacts on poverty reduction: however, deconcentration was limited due to the fact that the general strategies of the project were not differentiated according to the inequality across jurisdictions. To decentralize the Ministry of Health effectively, the federation must formulate objectives and strategies according to jurisdictional socioeconomic conditions and service need and capacity. Jurisdictions must be restructured and rescaled to improve their interaction with municipal governments, the health sector and the community.

Is E37, a major polypeptide of the inner membrane from plastid envelope, an S-adenosyl methionine-dependent methyltransferase?

Using antibodies raised against E37, one of the major polypeptides of the inner membrane from the chloroplast envelope, it has been demonstrated that a single immunologically related polypeptide was present in total protein extracts from various higher plants (monocots and dicots), in photosynthetic and non-photosynthetic tissues from young spinach plantlets, as well as in the cytoplasmic membrane from the cyanobacteria Synechococcus. This ubiquitous distribution of E37 strongly suggests that this protein plays an envelope-specific function common to all types of plastids. Comparison of tobacco and spinach E37 amino acid sequences deduced from the corresponding cDNA demonstrates that consensus motifs for S-adenosyl methionine-dependent methyltransferases are located in both sequences. This hypothesis was confirmed using a biochemical approach. It was demonstrated that E37, together with two minor spinach chloroplast envelope polypeptides of 32 and 39 kDa, can be specifically photolabeled with [3H]-S-adenosyl methionine upon UV-irradiation. Identification of E37 as a photolabeled polypeptide was established by immunoprecipitation. Furthermore, photolabeling of the three envelope polypeptides was specifically inhibited by very low concentration of S-adenosyl homocysteine, thus providing evidence for the presence within these proteins of S-adenosyl methionine- and S-adenosyl homocysteine-binding sites that were closely associated. Taken as a whole these results strongly suggest that E37 is an ubiquitous plastid envelope protein that probably has an S-adenosyl methionine-dependent methyltransferase activity. The 32 and 39 kDa envelope polypeptides probably have a similar methyltransferase activity.

[Burden of disease in the aged, Mexico, 1994]. / El peso de la enfermedad en adultos mayores, México 1994.

OBJECTIVE: To estimate the disability adjusted life years lost (DALYs) in population over 60 years of age in Mexico during 1994. MATERIAL AND METHODS: Years of life lost due to premature mortality (YLL) and years lived with disability (YLD) were estimated for 108 diseases, both sexes, and 32 states of the Mexican Republic divided in rural and urban areas in the population over 60 years of age, using the methodology originally proposed by Murray and López adapted to specific local characteristics. The inputs used were: mortality statistics for 1994 (after corrections of under-registration and misclassification), statistics on incidence and prevalence from local epidemiological studies, national health surveys and estimates by the authors. RESULTS: During 1994 the Mexican population over 60 years of age lost 1.8 million DALYs, 59% of which were YLL while 41% were YLD. Most of the burden of disease is due to noncommunicable diseases. The principal health needs of the elderly in Mexico can be divided in two groups: a) those that traditionally are frequent in this age group, such as ischaemic heart disease, diabetes, stroke and b) disabling diseases such as dementia, falls and arthritis as the most important. CONCLUSIONS: The use of composite indicators such as DALYs to assess health needs in older adult can help decision-makers and planners to incorporate disabling and lethal diseases within the list of priority needs, thereby achieving greater equity in the assignment of resources to different health care, prevention and rehabilitation programs.

Sequence and expression of the mRNA encoding HSP22, the mitochondrial small heat-shock protein in pea leaves.

A 3 h treatment at 40 degrees C of pea (Pisum sativum var. Douce Provence) plants induces production and accumulation of a small heat-shock protein of 22 kDa apparent molecular mass, designated HSP22, in the matrix compartment of mitochondria [Lenne and Douce (1994) Plant Physiol. 105, 1255-1261]. We show here that the HSP22 precursor (i.e. the mature protein plus the transit peptide) has an apparent molecular mass of 26 kDa after in vitro translation of mRNA extracted from heat-stressed pea plants and immunodetection. We have isolated, cloned and sequenced the full-length cDNA encoding the precursor of the mitochondrial HSP22. An analysis of the amino acid sequence of the mitochondrial HSP22 reveals that this protein is a representative member of the low-molecular-mass heat shock protein (HSP) superfamily, exhibiting the specific consensus regions that are typical of the small HSPs. Most importantly, comparison of the mitochondrial HSP22 sequence with that of chloroplast small HSPs indicates that HSP22 does not contain the typical chloroplast consensus region III. We have also analysed the kinetics of HSP22 induction, and report results on the temporal expression of HSP22 at the transcriptional level. HSP22 mRNA was detected as soon as 10 min after the temperature was raised to a high temperature of 40 degrees C. Then the amount of HSP22 mRNA declined considerably even though pea plants were still submitted to the heat treatment. These results are discussed in light of the translation data previously published [Lenne and Douce (1994) Plant Physiol. 105, 1255-1261], particularly concerning the physiological behaviour of mitochondria when plants are heat-stressed. Furthermore, we have studied the dependence of HSP22 accumulation with temperature and demonstrate that the pea mitochondrial heat-shock response is only developed under extreme environmental growth conditions.

The catalytic site of monogalactosyldiacylglycerol synthase from spinach chloroplast envelope membranes. Biochemical analysis of the structure and of the metal content.

We have analyzed the structure of the active site of monogalactosyldiacylglycerol (MGDG) synthase from spinach chloroplast envelope. Since purification of this membrane-embedded enzyme yielded such low amounts of protein that analyses of the amino acid sequence were so far impossible, we used indirect strategies. Analyses of the inhibition of MGDG synthase by UDP and of its inactivation by citraconic anhydride first indicated that the enzyme contained two functionally independent and topologically distinct binding sites for each substrate. Whereas MGDG synthase binds both the nucleotidic part of UDP-Gal and the acyl chains of 1,2-diacylglycerol, UDP is a competitive inhibitor relatively to UDP-Gal, while it does not compete with 1,2-diacylglycerol for binding on the enzyme. The UDP-Gal-binding site contains lysine residues, as demonstrated for UDP-Gal-binding sites from all galactosyltransferases studied so far. Radiolabeling of MGDG synthase by sulfur labeling reagent, a 35S-labeled lysine-blocking reagent, confirmed that MGDG synthase was a polypeptide with a low molecular mass (around 20 kDa). The 1,2-diacylglycerol-binding site contains reduced cysteines and at least one metal. The divalent cation(s) associated to apo-MGDG synthase was not unambiguously identified, but the results suggest that it could be zinc. Therefore, MGDG synthase presents some structural features in common with diacylglycerol-manipulating enzymes, such as protein kinase C and 1,2-diacylglycerol kinase, which are characterized by the presence of a ubiquitous Cys6His2 domain involved in zinc coordination in their 1,2-diacylglycerol-binding domains.

The outer membrane protein E24 of spinach chloroplast envelope: cloning of a cDNA and topological insertion of the protein in the membrane.

A cDNA coding for the outer membrane protein E24 of spinach chloroplast envelope has been obtained by screening an expression library of spinach cDNA with polyclonal antibodies. Analysis of the protein sequence and comparison with the thermolysin susceptibility of E24 in the chloroplast in situ suggest that E24 is a transmembrane protein and show that its NH2 terminal end is located on the cytosolic side of chloroplasts.

Comparison of the kinetic properties of MGDG synthase in mixed micelles and in envelope membranes from spinach chloroplast.

We have applied the 'membrane partition' kinetic modelling approach proposed by Heirwegh et al. [(1988) Biochem. J. 254, 101-108] to MGDG synthase in isolated envelope vesicles. Comparison of the kinetic parameters obtained for MGDG synthase assayed in purified envelope membranes and in mixed-micelles demonstrates that the latter are relevant to the situation in envelope membranes and that MGDG synthase has a very high affinity for dilinoleoylglycerol. Our results provide additional evidence for the hypothesis that the high affinity of the envelope MGDG synthase for dilinoleoylglycerol could be responsible for the presence of C18 fatty acids at both the sn-1 and sn-2 position of the glycerol backbone in MGDG.

[A community referral system for the permanent program of universal vaccination]. / Sistema comunitario de referencia para el programa continuo de vacunación universal.

This article describes a community referral system for the permanent immunization program, tested in Tijuana, Baja California, Mexico, by the Regional Nucleus for Health Systems Development (NUREDESS-Norte). The model was designed to facilitate the participation of the intermediate organizations that make up the community in urban settings. Through appropriate technology, health counselors identify with precision, ease and rapidity the specific immunization needs of pre-school age children. The counselors also help diminish the barriers in the way to service access, and follow-up the children at highest risk.

[Essential research in health systems]. / La investigación esencial en sistemas de salud.

Public health research and education in Mexico require further decentralization to improve its availability, quality and relevance for the development of local health systems. This article presents the experience of the Northern Regional Center for Health Systems Development (Nuredess-Norte), a consortium for the decentralization and regionalization of public health research and education of El Colegio de la Frontera Norte and the National Institute of Public Health. Nuredess-Norte initiated its activities in 1990 establishing a binational network of health systems consultants along the border, following a common methodology to improve health system quality through research. Later a Health Systems Development Teaching Program was established at the level of specialization with a high degree of decentralization and linkage with local health systems. Nuredess-Norte undertakes research, design and evaluation of innovations along the US-Mexico border. Emphasis is given to community participation and the development of primary health care.

Access policies and utilization patterns in prenatal and child delivery care in Mexico.

In Mexico, people utilize public, private and traditional health providers interchangeably and in contrast to official access policies. Access policies for prenatal and child delivery services are evaluated using data from the National Health Survey of 1988. The study documents significant coverage gaps on the part of public providers with respect to their potential coverage, and especially, large cross-utilization of social security, Ministry of Health and private providers by beneficiaries. Child deliveries in Mexico are attended by a physician in only 66% of cases. The percentages are 85% for social security affiliates, 53% for women within reach of IMSS-Solidarity services (a relief programme for the rural poor) and only 31% for women with official access to private or Ministry of Health care, or beyond the reach of services. Seventy-eight per cent of medical deliveries by women affiliated to social security occur at their pre-paid facilities, while 14% deliver at extra cost with private physicians, contributing to 32% of deliveries so offered. Even though only 7% of insured women deliver at Ministry of Health facilities, this amounts to 20% of the Ministry's relief offer. In all, only 66% of affiliates use social security delivery services. On the other hand, 36% of deliveries by non-insured women are cared for by Ministry of Health providers, and 39% by the private sector; 22% of such deliveries occur in social security institutions, amounting to 18% of these institutions' care offer. These results indicate a wide departure between policy and fact, and the working of distributive and redistributive forces that impinge on the quality and efficiency of health care. Open access to the reproductive health services of all public institutions, with coordination among them and private providers, is suggested as a possible solution.

Kinetic properties of monogalactosyldiacylglycerol synthase from spinach chloroplast envelope membranes.

We have investigated the functioning of monogalactosyldiacylglycerol (MGDG) synthase activity partially purified from spinach chloroplast envelope membranes, using mixed micelles containing diacylglycerol (the substrate for MGDG synthase), CHAPS (3-[(cholamidopropyl)dimethylammonio]-1- propanesulfonic acid), and phosphatidylglycerol. The presence of this anionic phospholipid was essential for optimal MGDG synthase activity because it strongly improves diacylglycerol solubilization by CHAPS. We have demonstrated that the "surface dilution" kinetic model proposed by Deems et al. (Deems, R.A., Eaton, B.R., and Dennis, E.A. (1975) J. Biol. Chem. 250, 9013-9020) is valid for MGDG synthase assayed in mixed micelles within a narrow range of CHAPS concentration. However, the experimental conditions we have set up in this study led to the description of defined equilibrium and kinetic parameters of the interaction of the envelope MGDG synthase with diacylglycerol. Two-substrate kinetic studies were performed with varied UDP-galactose molar concentrations and varied dioleoylglycerol surface concentrations. The families of reciprocal plots obtained were shown to intersect at a single point of the 1/[substrate] axis thus demonstrating that MGDG synthase is a sequential, either random or ordered, bireactant system. Therefore, MGDG synthase possesses two distinct and independent substrate-binding sites, a hydrophilic one for UDP-galactose and a hydrophobic one for diacylglycerol. The dependence of kinetic parameters on the diacylglycerol mol fraction allows a comparison of the affinity of the enzyme for a wide range of diacylglycerol molecular species. The Km values obtained were ranging between 0.0089 mol fraction (52 microM) for dilinoleoylglycerol (18:2/18:2) to 0.0666 mol fraction (416 microM) for distearoylglycerol (18:0/18:0), but the differences observed were not really related to the unsaturation of the molecule since the Km value for dilinoleoylglycerol was much lower than that (0.040 mol fraction) for dilinoleoylglycerol (18:3/18:3). The Km values for dioleoylglycerol (18:1/18:1) and for the diacylglycerol molecular species synthesized within chloroplasts, i.e. containing 18:1/16:0, were in the average range, i.e. lower than 0.030 mol fraction (around 170 microM).