Prospects for biopolymer production in plants.

It is likely that during this century polymers based on renewable materials will gradually replace industrial polymers based on petrochemicals. This chapter gives an overview of the current status of research on plant biopolymers that are used as a material in non-food applications. We cover technical and scientific bottlenecks in the production of novel or improved materials, and the potential of using transgenic or alternative crops in overcoming these bottlenecks. Four classes of biopolymers will be discussed: starch, proteins, natural rubber, and poly-beta-hydroxyalkanoates. Renewable polymers produced by chemical polymerization of monomers derived from sugars, vegetable oil, or proteins, are not considered here.

Periodic fever, aphthous stomatitis, pharyngitis, cervical adenitis syndrome is linked to dysregulated monocyte IL-1β production.

BACKGROUND: The exact pathogenesis of the pediatric disorder periodic fever, aphthous stomatitis, pharyngitis, cervical adenitis (PFAPA) syndrome is unknown. OBJECTIVES: We hypothesized that PFAPA might be due to dysregulated monocyte IL-1β production linked to genetic variants in proinflammatory genes. METHODS: Fifteen patients with PFAPA syndrome were studied during and outside a febrile episode. Hematologic profile, inflammatory markers, and cytokine levels were measured in the blood. The capacity of LPS-stimulated PBMCs and monocytes to secrete IL-1β was assessed by using ELISA, and active IL-1β secretion was visualized by means of Western blotting. Real-time quantitative PCR was performed to assess cytokine gene expression. DNA was screened for variants of the MEFV, TNFRSF1A, MVK, and NLRP3 genes in a total of 57 patients with PFAPA syndrome. RESULTS: During a febrile attack, patients with PFAPA syndrome revealed significantly increased neutrophil counts, erythrocyte sedimentation rates, and C-reactive protein, serum amyloid A, myeloid-related protein 8/14, and S100A12 levels compared with those seen outside attacks. Stimulated PBMCs secreted significantly more IL-1β during an attack (during a febrile episode, 575 ± 88 pg/mL; outside a febrile episode, 235 ± 56 pg/mL; P < .001), and this was in the mature active p17 form. IL-1β secretion was inhibited by ZYVAD, a caspase inhibitor. Similar results were found for stimulated monocytes (during a febrile episode, 743 ± 183 pg/mL; outside a febrile episode, 227 ± 92 pg/mL; P < .05). Genotyping identified variants in 15 of 57 patients, with 12 NLRP3 variants, 1 TNFRSF1A variant, 4 MEFV variants, and 1 MVK variant. CONCLUSION: Our data strongly suggest that IL-1β monocyte production is dysregulated in patients with PFAPA syndrome. Approximately 20% of them were found to have NLRP3 variants, suggesting that inflammasome-related genes might be involved in this autoinflammatory syndrome.

Positive control of swarming, rhamnolipid synthesis, and lipase production by the posttranscriptional RsmA/RsmZ system in Pseudomonas aeruginosa PAO1.

In Pseudomonas aeruginosa, the small RNA-binding, regulatory protein RsmA is a negative control element in the formation of several extracellular products (e.g., pyocyanin, hydrogen cyanide, PA-IL lectin) as well as in the production of N-acylhomoserine lactone quorum-sensing signal molecules. RsmA was found to control positively the ability to swarm and to produce extracellular rhamnolipids and lipase, i.e., functions contributing to niche colonization by P. aeruginosa. An rsmA null mutant was entirely devoid of swarming but produced detectable amounts of rhamnolipids, suggesting that factors in addition to rhamnolipids influence the swarming ability of P. aeruginosa. A small regulatory RNA, rsmZ, which antagonized the effects of RsmA, was identified in P. aeruginosa. Expression of the rsmZ gene was dependent on both the global regulator GacA and RsmA, increased with cell density, and was subject to negative autoregulation. Overexpression of rsmZ and a null mutation in rsmA resulted in quantitatively similar, negative or positive effects on target genes, in agreement with a model that postulates titration of RsmA protein by RsmZ RNA.

Report of the National Taskforce on Obesity: Obesity - the policy challenges: Executive Summary

The prevalence of overweight and obesity has increased with alarming speed over the past twenty years. It has recently been described by the World Health Organisation as a ‘global epidemic’. In the year 2000 more than 300 million people worldwide were obese and it is now projected that by 2025 up to half the population of the United States will be obese if current trends are maintained. The disease is now a major public health problem throughout Europe. In Ireland at the present time 39% of adults are overweight and 18% are obese. Of these, slightly more men than women are obese and there is a higher incidence of the disease in lower socio-economic groups. Most worrying of all is the fact that childhood obesity has reached epidemic proportions in Europe, with body weight now the most prevalent childhood disease. While currently there are no agreed criteria or standards for assessing Irish children for obesity some studies are indicating that the numbers of children who are significantly overweight have trebled over the past decade. Extrapolation from authoritative UK data suggests that these numbers could now amount to more than 300,000 overweight and obese children on the island of Ireland and they are probably rising at a rate of over 10,000 per year. A balance of food intake and physical activity is necessary for a healthy weight. The foods we individually consume and our participation in physical activity are the result of a complex supply and production system. The growing research evidence that energy dense foods promote obesity is impressive and convincing. These are the foods that are high in fat, sugar and starch. Of these potentially the most significant promoter of weight gain is fat and foods from the top shelf of the food pyramid including spreads (butter and margarine), cakes and biscuits, and confectionery, when combined are the greatest contributors to fat intake in the Irish diet. In company with their adult counterparts Irish children are also consuming large amounts of energy dense foods outside the home. A recent survey revealed that slightly over half of these children ate sweets at least once a day and roughly a third of them had fizzy drinks and crisps with the same regularity. Sugar sweetened carbonated drinks are thought to contribute to obesity and for this reason the World Health Organisation has expressed serious concerns at the high and increasing consumption of these drinks by children. Physical activity is an important determinant of body weight. Over recent decades there has been a marked decline in demanding physical work and this has been accompanied by more sedentary lifestyles generally and reduced leisure-time activity. These observable changes, which are supported by data from most European countries and the United States, suggest that physical inactivity has made a significant impact on the increase in overweight and obesity being seen today. It is now widely accepted that adults shoud be involved in 45-60 minutes, and children should be involved in at least 60 minutes per day of moderate physical activity in order to prevent excess weight gain. Being overweight today not only signals increased risk of medical problems but also exposes people to serious psychosocial problems due mainly to widespread prejudice against fat people. Prejudice against obese people seems to border on the socially acceptable in Ireland. It crops up consistently in surveys covering groups such as employers, teachers, medical and healthcare personnel, and the media. It occurs among adolescents and children, even very young children. Because obesity is associated with premature death, excessive morbidity and serious psychosocial problems the damage it causes to the welfare of citizens is extremely serious and for this reason government intervention is necessary and warranted. In economic terms, a figure of approximately â,¬30million has been estimated for in-patient costs alone in 2003 for a number of Irish hospitals. This year about 2,000 premature deaths in Ireland will be attributed to obesity and the numbers are growing relentlessly. Diseases which proportionally more obese people suffer from than the general population include hypertension, type 2 diabetes, angina, heart attack and osteoarthritis. There are indirect costs also such as days lost to the workplace due to illness arising from obesity and output foregone as a result of premature death. Using the accepted EU environmental cost benefit method, these deaths alone may be costing the state as much as â,¬4bn per year. The social determinants of physical activity include factors such as socio-economic status, education level, gender, family and peer group influences as well as individual perceptions of the benefits of physical activity. The environmental determinants include geographic location, time of year, and proximity of facilities such as open spaces, parks and safe recreational areas generally. The environmental factors have not yet been as well studied as the social ones and this research gap needs to be addressed. Clearly there is a public health imperative to ensure that relevant environmental policies maximise opportunities for active transport, recreational physical activity and total physical activity. It is clear that concerted policy initiatives must be put in place if the predominantly negative findings of research regarding the determinants of food consumption and physical activity are to be accepted, and they must surely be accepted by government if the rapid increase in the incidence of obesity with all its negative consequences for citizens is to be reversed. So far actions surrounding nutrition policies have concentrated mostly on actions that are within the remit of the Department of Health and Children such as implementing the dietary guidelines. These are important but government must now look at the totality of policies that influence the type and supply of food that its citizens eat and the range and quality of opportunities that are available to citizens to engage in physical activity. This implies a fundamental examination of existing agricultural, industrial, economic and other policies and a determination to change them if they do not enable people to eat healthily and partake in physical activity. The current crisis in obesity prevalence requires a population health approach for adults and children in addition to effective weight-reduction management for individuals who are severely overweight. This entails addressing the obesogenic environment where people live, creating conditions over time which lead to healthier eating and more active living, and protecting people from the widespread availability of unhealthy food and beverage options in addition to sedentary activities that take up all of their leisure time. People of course have a fundamental right to choose to eat what they want and to be as active as they wish. That is not the issue. What the National Taskforce on Obesity has had to take account of is that many forces are actively impeding change for those well aware of the potential health and well-being consequences to themselves of overweight and obesity. The Taskforce’s social change strategy is to give people meaningful choice. Choice, or the capacity to change (because the strategy is all about change), is facilitated through the development of personal skills and preferences, through supportive and participative environments at work, at school and in the local community, and through a dedicated and clearly communicated public health strategy. High-level cabinet support will be necessary to implement the Taskforce’s recommendations. The approach to implementation must be characterised by joined-up thinking, real practical engagement by the public and private sectors, the avoidance of duplication of effort or crosspurpose approaches, and the harnessing of existing strategies and agencies. The range of government departments with roles to play is considerable. The Taskforce outlines the different contributions that each relevant department can make in driving its strategy forward. It also emphasises its requirement that all phases of the national strategy for healthy eating and physical activity are closely monitored, analysed and evaluated. The vision of the Taskforce is expressed as: An Irish society that enables people through health promotion, prevention and care to achieve and maintain healthy eating and active living throughout their lifespan. Its high-level goals are expressed as follows: Its recommendations, over eighty in all, relate to actions across six broad sectors: high-level government; education; social and community; health; food, commodities, production and supply; and the physical environment. In developing its recommendations the Taskforce has taken account of the complex, multisectoral and multi-faceted determinants of diet and physical activity. This strategy poses challenges for government, within individual departments, inter-departmentally and in developing partnerships with the commercial sector. Equally it challenges the commercial sector to work in partnership with government. The framework required for such initiative has at its core the rights and benefits of the individual. Health promotion is fundamentally about empowerment, whether at the individual, the community or the policy level.

Obesity - the policy challenges: The report of the National Taskforce on Obesity

Click here to download PDF The prevalence of overweight and obesity has increased with alarming speed over the past twenty years. It has recently been described by the World Health Organisation as a ‘global epidemic’. In the year 2000 more than 300 million people worldwide were obese and it is now projected that by 2025 up to half the population of the United States will be obese if current trends are maintained. The disease is now a major public health problem throughout Europe. In Ireland at the present time 39% of adults are overweight and 18% are obese. Of these, slightly more men than women are obese and there is a higher incidence of the disease in lower socio-economic groups. Most worrying of all is the fact that childhood obesity has reached epidemic proportions in Europe, with body weight now the most prevalent childhood disease. While currently there are no agreed criteria or standards for assessing Irish children for obesity some studies are indicating that the numbers of children who are significantly overweight have trebled over the past decade. Extrapolation from authoritative UK data suggests that these numbers could now amount to more than 300,000 overweight and obese children on the island of Ireland and they are probably rising at a rate of over 10,000 per year. A balance of food intake and physical activity is necessary for a healthy weight. The foods we individually consume and our participation in physical activity are the result of a complex supply and production system. The growing research evidence that energy dense foods promote obesity is impressive and convincing. These are the foods that are high in fat, sugar and starch. Of these potentially the most significant promoter of weight gain is fat and foods from the top shelf of the food pyramid including spreads (butter and margarine), cakes and biscuits, and confectionery, when combined are the greatest contributors to fat intake in the Irish diet. In company with their adult counterparts Irish children are also consuming large amounts of energy dense foods outside the home. A recent survey revealed that slightly over half of these children ate sweets at least once a day and roughly a third of them had fizzy drinks and crisps with the same regularity. Sugar sweetened carbonated drinks are thought to contribute to obesity and for this reason the World Health Organisation has expressed serious concerns at the high and increasing consumption of these drinks by children. Physical activity is an important determinant of body weight. Over recent decades there has been a marked decline in demanding physical work and this has been accompanied by more sedentary lifestyles generally and reduced leisure-time activity. These observable changes, which are supported by data from most European countries and the United States, suggest that physical inactivity has made a significant impact on the increase in overweight and obesity being seen today. It is now widely accepted that adults shoud be involved in 45-60 minutes, and children should be involved in at least 60 minutes per day of moderate physical activity in order to prevent excess weight gain. Being overweight today not only signals increased risk of medical problems but also exposes people to serious psychosocial problems due mainly to widespread prejudice against fat people. Prejudice against obese people seems to border on the socially acceptable in Ireland. It crops up consistently in surveys covering groups such as employers, teachers, medical and healthcare personnel, and the media. It occurs among adolescents and children, even very young children. Because obesity is associated with premature death, excessive morbidity and serious psychosocial problems the damage it causes to the welfare of citizens is extremely serious and for this reason government intervention is necessary and warranted. In economic terms, a figure of approximately â,¬30million has been estimated for in-patient costs alone in 2003 for a number of Irish hospitals. This year about 2,000 premature deaths in Ireland will be attributed to obesity and the numbers are growing relentlessly. Diseases which proportionally more obese people suffer from than the general population include hypertension, type 2 diabetes, angina, heart attack and osteoarthritis. There are indirect costs also such as days lost to the workplace due to illness arising from obesity and output foregone as a result of premature death. Using the accepted EU environmental cost benefit method, these deaths alone may be costing the state as much as â,¬4bn per year. The social determinants of physical activity include factors such as socio-economic status, education level, gender, family and peer group influences as well as individual perceptions of the benefits of physical activity. The environmental determinants include geographic location, time of year, and proximity of facilities such as open spaces, parks and safe recreational areas generally. The environmental factors have not yet been as well studied as the social ones and this research gap needs to be addressed. Clearly there is a public health imperative to ensure that relevant environmental policies maximise opportunities for active transport, recreational physical activity and total physical activity. It is clear that concerted policy initiatives must be put in place if the predominantly negative findings of research regarding the determinants of food consumption and physical activity are to be accepted, and they must surely be accepted by government if the rapid increase in the incidence of obesity with all its negative consequences for citizens is to be reversed. So far actions surrounding nutrition policies have concentrated mostly on actions that are within the remit of the Department of Health and Children such as implementing the dietary guidelines. These are important but government must now look at the totality of policies that influence the type and supply of food that its citizens eat and the range and quality of opportunities that are available to citizens to engage in physical activity. This implies a fundamental examination of existing agricultural, industrial, economic and other policies and a determination to change them if they do not enable people to eat healthily and partake in physical activity. The current crisis in obesity prevalence requires a population health approach for adults and children in addition to effective weight-reduction management for individuals who are severely overweight. This entails addressing the obesogenic environment where people live, creating conditions over time which lead to healthier eating and more active living, and protecting people from the widespread availability of unhealthy food and beverage options in addition to sedentary activities that take up all of their leisure time. People of course have a fundamental right to choose to eat what they want and to be as active as they wish. That is not the issue. What the National Taskforce on Obesity has had to take account of is that many forces are actively impeding change for those well aware of the potential health and well-being consequences to themselves of overweight and obesity. The Taskforce’s social change strategy is to give people meaningful choice. Choice, or the capacity to change (because the strategy is all about change), is facilitated through the development of personal skills and preferences, through supportive and participative environments at work, at school and in the local community, and through a dedicated and clearly communicated public health strategy. High-level cabinet support will be necessary to implement the Taskforce’s recommendations. The approach to implementation must be characterised by joined-up thinking, real practical engagement by the public and private sectors, the avoidance of duplication of effort or crosspurpose approaches, and the harnessing of existing strategies and agencies. The range of government departments with roles to play is considerable. The Taskforce outlines the different contributions that each relevant department can make in driving its strategy forward. It also emphasises its requirement that all phases of the national strategy for healthy eating and physical activity are closely monitored, analysed and evaluated. The vision of the Taskforce is expressed as: An Irish society that enables people through health promotion, prevention and care to achieve and maintain healthy eating and active living throughout their lifespan. Its high-level goals are expressed as follows: Its recommendations, over eighty in all, relate to actions across six broad sectors: high-level government; education; social and community; health; food, commodities, production and supply; and the physical environment. In developing its recommendations the Taskforce has taken account of the complex, multisectoral and multi-faceted determinants of diet and physical activity. This strategy poses challenges for government, within individual departments, inter-departmentally and in developing partnerships with the commercial sector. Equally it challenges the commercial sector to work in partnership with government. The framework required for such initiative has at its core the rights and benefits of the individual. Health promotion is fundamentally about empowerment, whether at the individual, the community or the policy level.

Production of low phytic acid rice by hairpin RNA- and artificial microRNA-mediated silencing of OsMIK in seeds

To produce agronomically competitive rice with nutritionally superior, environmentally safe phytic acid (PA) levels, hairpin RNA (hpRNA)- and artificial microRNA (amiRNA)-mediated gene silencing approaches were explored to reduce both myo-inositol kinase gene (OsMIK) expression and PA accumulation in rice seeds. hpRNA and amiRNA sequences targeted to OsMIK (hpMIK and amiMIK), under the control of a rice Ole18 promoter, were transformed into the rice cultivar Nippon-bare. Fourteen and 21 independent transgenic events were identified containing the hpMIK and amiMIK constructs, respectively, from which five stable homozygous transgenic lines of each were developed together with their null siblings. Southern blotting demonstrated transgene integration into the genome and quantitative real-time PCR showed that gene silencing was restricted to seeds. OsMIK transcripts were significantly reduced in both transgenic amiMIK and hpMIK seeds, which had PA levels reduced by 14.9-50.2 and 38.1-50.7 %, respectively, compared with their respective null siblings. There were no systematic significant differences in agronomic traits between the transgenic lines and their non-transgenic siblings, and no correlation between seed PA contents and decreased rates of seed germination and seedling emergence. The results of the present study suggest that Ole 18-driven OsMIK silencing via hpRNA and amiRNA could be an effective way to develop agronomically competitive low phytic acid rice.

Production of amastigotes from metacyclic trypomastigotes of Trypanosoma cruzi

Attempts to recreate all the developmental stages of Trypanosoma cruzi in vitro have thus far been met with partial success. It is possible, for instance, to produce trypomastigotes in tissue culture and to obtain metacyclic trypomastigotes in axenic conditions. Even though T. cruzi amastigotes are known to differentiate from trypomastigotes and metacyclic trypomastigotes, it has only been possible to generate amastigotes in vitro from the tissue-culture-derived trypomastigotes. The factors and culture conditions required to trigger the transformation of metacyclic trypomastigotes into amastigotes are as yet undetermined. We show here that pre-incubation of metacyclic trypomastigotes in culture (MEMTAU) medium at 37°C for 48 h is sufficient to commit the parasites to the transformation process. After 72 h of incubation in fresh MEMTAU medium, 90% of the metacyclic parasites differentiate into forms that are morphologically indistinguishable from normal amastigotes. SDS-PAGE, Western blot and PAABS analyses indicate that the transformation of axenic metacyclic trypomastigotes to amastigotes is associated with protein, glycoprotein and antigenic modifications. These data suggest that (a) T. cruzi amastigotes can be obtained axenically in large amounts from metacyclic trypomastigotes, and (b) the amastigotes thus obtained are morphological, biological and antigenically similar to intracellular amastigotes. Consequently, this experimental system may facilitate a direct, in vitro assessment of the mechanisms that enable T. cruzi metacyclic trypomastigotes to transform into amastigotes in the cells of mammalian hosts.

Studies on the production and regulation of interleukin, IL-13, IL-4 and interferon-gamma in human Schistosomiasis mansoni

The production and regulation of interleukin (IL) IL-13, IL-4 and interferon-gamma was evaluated in different clinical forms of human schistosomiasis. The mechanisms of immune regulation are apparently different in the various clinical stages of the disease, some of them being antigen specific.

Geographic distribution and morphometric differentiation of Triatoma nitida usinger 1939 (Hemiptera: Reduviidae: Triatominae) in Guatemala

Triatoma nitida was found in 14 (0.4%) out of 3,726 houses located in six departments across Guatemala, which were surveyed from 1994 to 1998 by the man-hour collection method. Compared to previous information, the distribution of T. nitida in Guatemala has increased from five to nine departments; the species is present in mild climates at altitudes from 960 to 1,500 m. Fourteen percent of the intradomestic T. nitida were infected with Trypanosoma cruzi. The species was often found in conjunction with other triatomines (T. dimidiata and Rhodnius prolixus). The domestic and peridomestic presence of T. nitida in Guatemala was rare, but occasionally this species was colonizing human-made constructions. T. nitida appears to have a low importance as Chagas disease vector in Guatemala, as indicated by its scarce presence in the domestic habitats and defecation patterns. However, it clearly has potential to become a Chagas vector so we recommend an on-going study of the intradomestic presence of T. nitida following the control programs in Guatemala. Morphometric analysis of 47 T. nitida males from three localities showed quantitative differences between the populations, which indicates that geographic distance is an important factor in the structuring of T. nitida populations.

Factors Supporting Cysteine Tolerance and Sulfite Production in Candida albicans.

The amino acid cysteine has long been known to be toxic at elevated levels for bacteria, fungi, and humans. However, mechanisms of cysteine tolerance in microbes remain largely obscure. Here we show that the human pathogenic yeast Candida albicans excretes sulfite when confronted with increasing cysteine concentrations. Mutant construction and phenotypic analysis revealed that sulfite formation from cysteine in C. albicans relies on cysteine dioxygenase Cdg1, an enzyme with similar functions in humans. Environmental cysteine induced not only the expression of the CDG1 gene in C. albicans, but also the expression of SSU1, encoding a putative sulfite efflux pump. Accordingly, the deletion of SSU1 resulted in enhanced sensitivity of the fungal cells to both cysteine and sulfite. To study the regulation of sulfite/cysteine tolerance in more detail, we screened a C. albicans library of transcription factor mutants in the presence of sulfite. This approach and subsequent independent mutant analysis identified the zinc cluster transcription factor Zcf2 to govern sulfite/cysteine tolerance, as well as cysteine-inducible SSU1 and CDG1 gene expression. cdg1Δ and ssu1Δ mutants displayed reduced hypha formation in the presence of cysteine, indicating a possible role of the newly proposed mechanisms of cysteine tolerance and sulfite secretion in the pathogenicity of C. albicans. Moreover, cdg1Δ mutants induced delayed mortality in a mouse model of disseminated infection. Since sulfite is toxic and a potent reducing agent, its production by C. albicans suggests diverse roles during host adaptation and pathogenicity.

High antigen concentration inhibits T cell proliferation but not interleukin 2 production: examination of limiting dilution microcultures and T cell clones.

The effect of high antigen dose on the activation of cytochrome c peptide-primed lymph node cells was determined in several strains of mice by a limiting dilution analysis. It was found that proliferation of cytochrome c peptide-specific T cells was completely inhibited at high antigen concentration in C57BL/6 but only partially in DBA mice and had no effect in SJL mice. Clones derived from DBA mice showed a differential capacity to be inhibited by high antigen dose. On the other hand, interleukin 2 production by these clones was not impaired regardless of the antigen concentrations used.

Down-modulation of lymphoproliferation and interferon-gamma production by beta-glucan derived from Saccharomyces cerevisiae

beta-glucan, one of the major cell wall components of Saccharomyces cerevisiae, has been found to enhance immune functions. This study investigated in vivo and in vitro effects of beta-glucan on lymphoproliferation and interferon-gamma (IFN-gamma) production by splenic cells from C57BL/6 female mice. All experiments were performed with particulate beta-glucan derived from S. cerevisiae. Data demonstrated that both, i.p administration of particulate beta-glucan (20 or 100 µg/animal) and in vitro stimulation of splenic cells (20 or 100 µg/ml of culture) decreased lymphoproliferation and IFN-gamma production induced by concanavalin A. These results suggest that beta-glucan can trigger a down-modulatory effect regulating a deleterious immune system hyperactivity in the presence of a strong stimulus.