Murine cytomegalovirus infection inhibits tumor necrosis factor alpha responses in primary macrophages

Despite robust host immune responses the betaherpesvirus murine cytomegalovirus (MCMV) is able to establish lifelong infection. This capacity is due at least in part to the virus utilizing multiple immune evasion mechanisms to blunt host responses. Macrophages are an important cell for MCMV infection, dissemination, and latency despite expression in the host of multiple cytokines, including tumor necrosis factor alpha (TNF-alpha), that can induce an antiviral state in macrophages or other cells. In this study, we found that MCMV infection of bone marrow-derived macrophages inhibited TNF-alpha-induced ICAM-1 surface expression and mRNA expression in infected cells via expression of immediate early and/or early viral genes. MCMV infection blocked TNF-alpha-induced nuclear translocation of NF-kappaB. This inhibition of TNF-alpha signaling was explained by a decrease in TNF receptor 1 (TNFR1) and TNFR2 that was due to decreased mRNA for the latter. These findings provide a mechanism by which MCMV can evade the effects of an important host cytokine in macrophages.     

Deactivation of endothelium and reduction in angiogenesis in psoriatic skin and synovium by low dose infliximab therapy in combination with stable methotrexate therapy: a prospective single-centre study

Psoriasis and psoriatic arthritis are inflammatory diseases that respond well to anti-tumour necrosis factor-α therapy. To evaluate the effects of anti-tumour necrosis factor-α treatment on expression of adhesion molecules and angiogenesis in psoriatic lesional skin and synovial tissue, we performed a prospective single-centre study with infliximab therapy combined with stable methotrexate therapy. Eleven patients with both active psoriasis and psoriatic arthritis received infusions of infliximab (3 mg/kg) at baseline, and at weeks 2, 6, 14 and 22 in an open-label study. In addition, patients continued to receive stable methotrexate therapy in dosages ranging from 5 to 20 mg/week. Clinical assessments, including Psoriasis Area and Severity Index (PASI) and Disease Activity Score (DAS), were performed at baseline and every 2 weeks afterward. In addition, skin biopsies from a target psoriatic plaque and synovial tissue biopsies from a target joint were taken before treatment and at week 4. Immunohistochemical analysis was performed to detect the number of blood vessels, the expression of adhesion molecules and the presence of vascular growth factors. Stained sections were evaluated by digital image analysis. At week 16, the mean PASI was reduced from 12.3 ± 2.4 at baseline to 1.8 ± 0.4 (P ≤ 0.02). The mean DAS was reduced from 6.0 ± 0.5 to 3.6 ± 0.6 (P ≤ 0.02). We found some fluctuations in DAS response as compared with the change in PASI, with the latter exhibiting a steady decrease over time. After 4 weeks the cell infiltrate was reduced in both skin and synovium. There was a significant reduction in the number of blood vessels in dermis and synovium at week 4. A significant reduction in the expression of α_vβ₃ integrin, a marker of neovascularization, was also found in both skin and synovium at week 4. In addition, a significant reduction in the expression of adhesion molecules was observed in both skin and synovium at week 4. We also observed a trend toward reduced expression of vascular endothelial growth factor in both skin and synovium. In conclusion, low-dose infliximab treatment leads to decreased neoangiogenesis and deactivation of the endothelium, resulting in decreased cell infiltration and clinical improvement in psoriasis and psoriatic arthritis.     

Ultrastructure of the septal complex in hyphae of Cryptococcus laurentii.

Electron microscopy of hyphae produced by Cryptococcus laurentii revealed typical basidiomycetous dolipore septa between the cells. Parenthesomes were not observed.     

DIHYDROGENATED ALKALOIDS OF ERGOT IN TREATMENT OF PERIPHERAL VASCULAR DISEASES

The dihydrogenated alkaloids of ergot, dihydroergocornine (DHO 180) and an equal mixture of dihydroergocornine, dihydroergocristine and dihydroergokryptine known as CCK 179 have been found to be therapeutic adjuncts in the medical treatment of peripheral vascular diseases. Their action is primarily that of adrenergic blockage, although depression of the brain stem is to be considered.The mixture of alkaloids (CCK 179) was found to be more effective than a single alkaloid, dihydroergocornine (DHO 180). A greater number of patients were benefited, relief of symptoms was greater and the dosage easier to establish. A favorable therapeutic response of clinical significance with the mixture was obtained in approximately 60 per cent of all cases investigated. It was of greater benefit in the organic occlusive diseases, where a larger percentage of favorable responses was obtained than in the purely vasospastic disorders.Orally and subcutaneously, CCK 179 exhibited vasodilating properties which compared favorably with paravertebral and peripheral nerve block, reflex heat, alcohol and sympathectomy. Surface temperatures were elevated, oscillometric readings increased and tolerance to cold increased in a statistically significant number of cases. Effects of sympathectomies were frequently enhanced. Following subcutaneous administration, increased surface temperatures of the extremities of one to two hours'' duration were obtained in 90 per cent of all cases.Paresthesias, nocturnal cramps and intermittent claudication were improved. A sense of well-being was occasionally exhibited.Blood pressure and pulse rates were rarely affected. Blood pressure was lowered in normotensive patients, but was rarely changed in hypertensive patients.Symptoms of overdosage appeared after two to three months of continuous therapy. These were manifested by lowered surface temperatures, decreased tolerance to cold, return of intermittent claudication and occasionally by vague general discomfort. These symptoms disappeared on cessation of therapy. Improvement frequently followed. In only one case was there an immediate reaction. Following subcutaneous administration of CCK, blood pressure and pulse rate increased and oscillometric readings and surface temperatures decreased.Frequent courses of therapy with interruptions were necessary for maintenance of improvement.     

Early diagnosis of ovarian cancer.

Ovarian cancer is the most common fatal gynecologic malignant disease. Unfortunately 60% to 70% of patients present initially with advanced disease. Progress in the treatment of this condition will be made only if it can be diagnosed early. Pelvic examination is still the best screening test despite attempts to make an early diagnosis with the use of cytology, ultrasonography, and serum determinations for fibrin degradation product; haptoglobin, protein-bound fucose and tumour-associated antigens. The best prospect for a screening test for ovarian cancer probably lies in the field of tumour immunology.     

Agricultural policies, food and public health

A historical view on how our agricultural systems evolved and how they are contributing to obesity and disease.What and how much we eat and drink has a significant influence on our health. This is evident in the epidemic of obesity sweeping across developed and developing nations alike, bringing in its wake a range of diseases including diabetes, coronary heart disease and some cancers. One main cause of this is a change in diet that has directly affected our health and well-being. For more than a century, Western governments have invested heavily in agricultural research and infrastructure with the aim of providing sufficient, affordable animal products and some basic cash crops. Accordingly, Western diets have shifted over the past century, in particular during the period following the Second World War, to include more animal-sourced foods—such as meat, poultry, dairy products, seafood and eggs—as well as more refined carbohydrates—that is, caloric sweeteners from a range of food crops including sugar cane, sugar beets and corn. During this same period, however, we have begun to realize that a healthy diet actually requires fewer animal products and refined carbohydrates and more vegetables, fruits, beans and whole grains. Redressing this balance is a complex task requiring not only a shift in agricultural investment and policy, but also changes in social preferences that have developed over decades, in part due to the relative cheapness of animal-sourced foods.Many groups offer specialized perspectives on food; ‘locavores'' and the slow food movement, public health advocates who want to ban sugar-sweetened beverages and other ‘junk'' or low-nutritional-value food, economists, agricultural scientists and other experts. My perspective as a global nutrition scientist and human-resource economist is to analyse the forces that have shaped our food supply in order to understand what we habitually eat and drink today. This could help to understand what it might take to improve imbalanced diets and recapture earlier and healthier eating patterns. It is therefore instructive to look at food, agriculture and diets from a historical perspective, as our health requirements and our understanding of the role of diet in health is different from earlier periods.Focusing on sugar and spices provides a useful example with which to begin the story of how our agricultural system and social preferences have evolvedThe discovery and exploration of the Americas—the New World—was driven by a desire to find faster and more efficient routes to the spice islands of Asia—the Old World—thereby circumventing the Muslim empires. In the course of this endeavour, the great European explorers first discovered and mapped the Caribbean islands, North and Central America and, eventually, the whole of the Americas. The economic exploitation of the Caribbean and what is today the USA began with sugar plantations and trade in rum and molasses—the search for gold started later (Fig 1).Open in a separate windowFigure 1The Atlantic trade routes between Africa, the New World and Europe. The ‘trade triangle'' was appealing to European (particularly British) merchants because each leg of the journey was profitable. Manufactured items such as guns, alcohol or cloth could be shipped to Africa, the traders would then pick up slaves to take to America and the West Indies, before finally returning to Europe with highly profitable food and raw materials including cod, sugar and molasses—which could be processed into rum.Focusing on sugar and spices provides a useful example with which to begin the story of how our agricultural system and social preferences have evolved. Both of these commodities have had an important historical role in the rise and fall of empires and, in some sense, between the fifteenth and nineteenth centuries sugar and spices dominated global trade. As an example of the importance of spices, the Dutch traded the island of Manhattan to the British in return for the island of Run in the Indonesian Banda Islands, where nutmeg was grown (Fig 2). Together with cod, sugar and spices drove nations to war and created the largest food-related conflicts of that period. During the seventeenth century alone, the trade of spice and sugar in the New and Old Worlds triggered violent clashes over territories and trade routes (Corn, 1998; Schwartz, 2004). By the end of the 1600s, European powers had managed to gain control of the global production and trade of these foods, with each country exploiting foreign resources and labour for their own wealth.Open in a separate windowFigure 2Purchase of Manhattan Island by Peter Minuit, September 1626. Oil on canvas by American School (Twentieth century). © Collection of the New York Historical Society, USA/ The Bridgeman Art Library.Nevertheless, the importance of these agricultural commodities to Europe both expanded production in the colonies and boosted research. Indeed, modern agricultural research was enabled by the work of scientists in the nineteenth century such as Justus von Liebig (1803–1873) in Giessen, Germany, who founded agricultural chemistry—in particular the use and effects of fertilizers—and Gregor Mendel (1822–1884), whose work on inheritance laid the scientific foundation for modern crop-breeding programmes and the field of genetics. Today, Giessen University has a museum about the origins of organic chemistry and the birth of modern fertilizer and, as an aside, the discovery that led to Marmite^™—much favoured in Britain and by many vegetarians (von Liebig, 1840). It was the work of these scientists and the contributions of others over the ensuing decades that eventually created the modern agricultural system (Gardner, 2002).In my quest to understand the history of agriculture and how government investment in food and research has shaped our diet, I have focused on the USA, which put forth its first systematic funding programme for agriculture in 1862. Sugar was one of the first crops to benefit from government money and by 1878 this investment had resulted in the successful cultivation of sugar beets in Maine and the first beet-sugar factory in California, only one year later. Outside the USA, research was funded to systematically increase the productivity of sugar plantations in the Caribbean and Indonesia. Cane-breeding research began in the 1880s in Java, at the Dutch East Java Research Station and in Barbados, at the British Dodds Botanical Station (Galloway, 1996, 2000).Many will argue that direct government support for farmers in the USA occurred mainly after the Second World War, but we should not dismiss the importance of earlier developments (Agricultural Research Service, 2007). These include the creation of the US Department of Agriculture in 1862 by the Abraham Lincoln administration, the authorization of public land grants for colleges to teach agriculture, the instigation of government research on animal diseases, the development of an array of agricultural cultivation techniques and tools, the import of Aberdeen Angus bulls from Scotland in 1873, the creation of feed mills and milking machines, the irrigation of arid lands, the first long-haul shipments of meat in refrigerated boxcars in 1888... we could go on.Another issue was the use of nitrogen fertilizers and the concomitant breeding of crops that were better suited to using it. Moreover, the development of hybrid corn, rust-resistant wheat and oats and insect-control programmes increased the production of feed for the livestock industry. Artificial insemination, controlled feeding, cross-breeding and disease control improvements for livestock, poultry and the dairy industry were all also developed in the 40 years before the war (Gardner, 2002). Finally, sugar remained an important commodity: for example, the Sugar Station—founded in 1885—is the oldest of the Louisiana Agricultural Experiment Stations.The agricultural sector undoubtedly had a crucial role in the development of the US economy and society. Railways to transport livestock, among other things, opened up the US mid-west and canals were built to move grain. During the nineteenth century, the majority of American workers were farmers and, although their numbers have declined during the twentieth century, they have retained their voice and influence; not only on the economy and politics, but also on the American psyche.The Soviet government strongly emphasized competition with the West, not only in space technology and science, but also in terms of diet and healthThe key issue with all of these developments is that much of the government funding and research focused on a few cash crops, particularly grains and animal-source foods. From 1850–1950, this focus was a result of politics and science and the most important economic crops received the greatest government support. However, despite the enormous advances between 1870 and 1945, there was actually little increase in the yield of key crops such as corn, wheat, potato and cotton (Cochrane, 1993).At the same time, nutritionists and other experts were beginning to take a closer look at diets, with the aim of improving health. Wilbur Olin Atwater (1844–1907), Carl Voit (1831–1908) and other scholars in the 1800s called for improvements in the diets of labourers, soldiers and workers in Western Europe and the USA, to include 100–200 g of protein each day. Studies in mice and other animals supported this recommendation, as animals that were fed more protein grew better. During this period, most medical and nutritional research therefore recommended an adequate supply of grains and other basic staples and encouraged the consumption of animal products, as the focus was on protein quality. Rare was the scientist, such as Weston Price, whose studies of isolated indigenous populations prompted him to promote a vegetarian diet, or at least a diet with minimal meat, grown in natural environments (Price, 1981).​).Open in a separate windowOil on canvas by Dutch School. Private Collection. Photo © Peter Nahum at The Leicester Galleries, London/ The Bridgeman Art LibraryThese nutritional ruminations were developed further in the former Soviet Union, where posters showed muscular workers with the phrase “Eat More Meat” (Popkin et al, 1997). The Soviet government strongly emphasized competition with the West, not only in space technology and science, but also in terms of diet and health. They essentially created a series of norms, standards and production targets to increase the outputs of the meat and dairy sectors of their economy. Russian nutritionists recommended a diet based on a ratio of 1 g of protein to 1 g of fat to 4 g of carbohydrate: they postulated that an average person should consume 120 grams of protein (55% from animal sources), 120 g of fat, and about 480 g of carbohydrate each day. Comments made by two general secretaries of the Communist Party and various heads of state illustrate this focus on animal proteins: “we plan the following increases in the consumption per capita: meat and meat products—2.5 times, milk and milk products—2 times [...] and some reduction in potato and bread consumption” (Kruschev, 1961). “The nature of the goals that must be achieved in the next five-year period determines the increasing responsibility of agricultural committees, rural party branches, collective [...] farms. [...] The average annual production of meat in the next 5 years must exceed 14 million tons, the production of milk must exceed 92 million tons, the production of eggs—46 billion pieces” (Brezhnev, 1967).The ‘eat meat'' approach to agriculture and trade that had been central to the Soviet post-War economy can explain what happened, to a lesser extent, in the WestUnfortunately, the insistence by Russian nutritionists that 55% of protein come from animal sources formed part of the scientific and legal bulwark that led, ultimately, to crippling agricultural subsidies in the former Soviet Union—by the end, half of the Union''s debt was attributed to agricultural spending and the other half to military spending.I got involved in the issue of the Soviet Recommended Daily Allowances (RDAs) as a member of the G7 team of economists, to help the former Soviet Union reform its economic system. A crucial feature was the high pensions and poverty levels that allowed 75% of Soviet citizens to receive transfer payments that were intended for the poor. These were based on the old Soviet RDAs that required high levels of animal protein (Brezhnev, 1967; Popkin et al, 1997). The governments of Michael Gorbachev and Boris Yeltsin made identifying and supporting the poor a priority, rather than those who could not afford the high meat and dairy requirements of the former Soviet RDAs. In order to create a revised food basket based on cheaper items that more people could afford, we had to revise these RDAs and lower the poverty line, to help the real poor (Zohoori et al, 1998; Lokshin & Popkin, 1999). This meant changing the RDAs and in turn facing off with politicians and labour unions who loved the high poverty line. The ‘eat meat'' approach to agriculture and trade that had been central to the Soviet post-War economy can explain what happened, to a lesser extent, in the West.After the Second World War and the initial focus on reconstruction in Europe, western European governments and the USA began to invest heavily in the agricultural sector. In terms of value-added per farmer, productivity grew from 1% annually in the 1900–1940 period to 2.8% per year. Investments were made in mechanization (Gardner, 2002) and farmer productivity rose rapidly. Soybean and other oilseed crops also became important as cheap and efficient ways to produce edible vegetable oils and animal feed (Williams, 1984; Popkin & Drewnowski, 1997).All of these changes were the result of enormous direct and indirect subsidies, but these were only a part of the total public investment. Marketing assistance, favourable tax policies, credit programmes and commodity programmes were all paid for by governments to enhance their agricultural sectors. Gardner (2002) has estimated that the total public investment in agriculture in 1940 was $500 billion, compared with $2.5 trillion in 1990 (based on the value of the US dollar in 1992). Various scholars have tried to quantify research inputs and their effects on agricultural output and they have found strong financial returns linked with all research benefits (Alston et al, 2009). Still, the total effect of the direct and indirect programmes, investments, tax policies, subsidies and so on has not been fully established. Nevertheless, the Organization for Economic Cooperation and Development (OECD) estimates that 29% of the income of farmers in Western countries—more than $283 billion in 2006, for example—comes from government subsidies, trade interventions or direct income transfers (Paarlberg, 2010).…although many educated, high-income Europeans and Americans have begun to shift to what is now felt to be a healthier diet, animal products remain central to a ‘healthy'' diet…A number of lower- and middle-income countries—led by Brazil, China and India—have tried to convince the USA and the EU to reduce agricultural subsidies and allow true competition in the global food market. The Doha Development Agenda (DDA), which commenced in November 2001 in Doha, Qatar, is the trade-negotiation round of the World Trade Organization. One of their initial key objectives was to lower agriculture trade barriers around the world, but as of 2008, talks have stalled. There is also considerable anger against and between the EU and the USA over their maintenance of agricultural subsidies—seen to be effectively barriers to trade. Farmers and their associations have also become effective lobbyists. Although their actions are not always as visible as the demonstrations of French farmers, they nonetheless curtail the ability of European and US politicians to reduce agricultural subsidies.This massive support of a farming system that has produced inexpensive animal food has not bankrupted the USA or Europe; nor has the emphasis on meat, dairy and animal protein consumption been followed as strictly and extensively as it was in the USSR. In the West, the goal has been to provide a healthy diet, defined as including adequate starchy staples such as bread and meaningful levels of animal-sourced foods: dairy, meat or poultry. In other words, the USA and Europe did not set out to achieve a fixed level of animal food consumption, but they achieved this anyway.In the 1960s, high-income, well-educated adults in the USA—especially white adults—consumed high-fat, high-meat diets, whereas lower-income adults consumed a healthier diet of mainly beans and vegetables (Popkin et al, 1996). Ancel Keys and others have shown how diets high in saturated fats contribute to heart disease (Keys, 1962), even though the received wisdom has been that such diets are good for you. More interestingly, although many educated, high-income Europeans and Americans have begun to shift to what is now felt to be a healthier diet, animal products remain central to a ‘healthy'' diet (Dansinger et al, 2005; Gardner et al, 2007; Sacks et al, 2009), as the focus on energy balance and weight seems to dominate.The 1960s also saw the appreciation and greater consumption of specialty crops including vegetables, fruits and beans. Scientists also began to understand the role of fibre in the diet, especially from whole grains. Alston et al (2009) have so far provided the best examination of the relationship between fruits, vegetables and beans and research funding. They have shown that these crops are most likely to be underfunded, in relation to their economic benefit. Mark Hegsted, an eminent nutritionist, showed the harmful effects of saturated fats from eggs and meat on cholesterol and the positive effects of unsaturated fats from nuts (Hegsted et al, 1965). He was behind the 1977 Dietary Goals for the USA, which set maximum levels for meat, dairy and egg intake and were heavily criticized by the animal food sector (Carter, 1977). Hegsted tried to encourage more consumption of fruits, grains and vegetables, a suggestion that was met by a barrage of criticism from lobby groups. Hegsted was so far ahead of his time that few nutritionists defended him: the financial interests of the pork, beef, dairy and poultry sectors won, and his tough guidelines were never truly implemented (Carter, 1977).Our agricultural system is still based on the earlier goals of consuming animal products and sugar, fats and oils—which are accepted by key segments of societyThe situation today is different, as the nutrition profession—faced with high obesity and diabetes rates, and the prevalence of related cardio-metabolic conditions, which are linked to our high-sugar and high-saturated-fat diet—is seeking major changes (US Department of Agriculture, 2010). Health scholars have begun to show that lower-quality ‘junk'' foods containing high levels of saturated fat and sugar are cheaper than healthier foods (Drewnowski & Darmon, 2005; Maillot et al, 2007). In other words, the health benefits and economic costs are completely out of line. Nevertheless, public funding of agriculture between 1970 and 2004 did not change to reflect this new understanding of the health impact of specialty crops.Although many of us love to eat local food, this approach will not address global problems…Our agricultural system is still based on the earlier goals of consuming animal products and sugar, fats and oils, which are accepted by key segments of society. This has led to a general conceptualization of how our agricultural system should evolve and what it should provide. Curiously, the father of modern nutrition and the initiator of the first food and nutrition division under the US agricultural research system, Wilbur Atwater, conducted his PhD dissertation on the composition of corn. He noted that, “our diet is one-sided and that we eat too much [...] fat, starch and sugar [...]. How much harm is done to our health by our one-sided diet [...]? No one can say” (Muller et al, 2007). The main question is therefore whether and how a change in agricultural research funding and policies could encourage a healthier diet, with a reduced focus on animal-sourced foods.I was recently at a meeting with organic farmers and others involved in local farmers'' markets in the USA and Canada. When I asked whether we could form local markets in every state of the union, my fellow attendees used the small Iowan town of Pocahontas as an example in their answer. I was told that in Pocahontas, it would be next to impossible to create a farmers'' market because the whole focus of agriculture there—irrigation, production, transportation and so on—is on corn and soybeans. It would be inordinately expensive for the farmers of Pocahontas to grow vegetables and fruits on their land. The farmers I spoke to also told me that the driving issue has been to reduce the cost of corn and soybeans, which form the basis of caloric sweeteners, as well as 80% of all vegetable oil produced. They also pointed out that this cheap supply of cash crops was the main engine that has driven the beef and poultry industries.Governments have invested a lot of money to research and develop these cash crops, making them as productive and inexpensive as possible. It is therefore not surprising that the world price for beef has declined from more than $530 for 220 pounds (100 kg) in 1970 to less than $190 for the same amount in 1995 (Fig 3). This is a global market price and not what we pay in the USA or the EU; it is a wholesale cost. Nevertheless, a similar decline has occurred for all of the commodities mentioned above—as a result of systematic assistance and guidance, administered in an array of ways.Open in a separate windowFigure 3Global prices for beef in 1990 US dollars. Source: International Food Price Research Institute, Washington, DC, USA.Will prices go up for these foods if we cut agricultural subsidies? I suspect so, but there is conflicting evidence. Many of the subsidies end up in the profit margins of agribusinesses. Although we might not expect them to absorb reductions in their profits, there is also no requirement for governments to subsidize their shareholders in this way.It seems that the broiler industry, for example, saved more than $11.25 billion between 1997 and 2005 because the price they paid for feed was 21% less than the cost of production (Starmer et al, 2006). Corn farmers made profits, but scholars have pointed out that the subsidies did not substantially increase the profits of the farmers, but rather benefited poultry agribusiness. These huge profits were also seen in the pork sector, where profits went to the big pork companies and not to the farmers (Starmer et al, 2006).This is the result of a long history of varied policies—all focused on helping farmers to grow key crops and agribusinesses to produce animal products. However, because the government provides money that supports this behaviour, corn farmers, chicken farmers and, particularly, large agribusiness—dominated by names such as Archer Daniels Midland and Cargill—are unlikely to change their ways. It is therefore not surprising to discover that during the past 30–40 years the price of corn and soybeans has declined, while the price of fruits and vegetables—which are on the whole unsubsidized—have increased (Hunt et al, 2007; Fig 4).Open in a separate windowFigure 4Development of relative prices for various foods in the USA from 1983 to 2005.We must realize that a huge disconnect exists between the prices farmers receive for a product and its retail cost. For instance, the prices that farmers receive for fruit and vegetables have declined in real terms during the past 40 years, but the prices that consumers pay have increased. In other words, farmers are not receiving the extra money—this goes to the middlemen, agribusinesses and major food chains. This has been shown nicely by one group of agricultural economists and it contradicts the naive thinking that agricultural policy—how much farmers are supported—is the sole cause of fruit and vegetable price dynamics. Due to the small proportion of food costs in the final costs of what we consume, we must question whether the agricultural system has anything at all to do with the cost of fruits and vegetables.In fact, this disconnect means agricultural subsidies are only part of the story of the politics and economics of the agricultural sector. It also means that although the European, American and global agricultural systems have been designed to facilitate the cheap production of animal products, we do not fully understand how to reverse this situation and return to a healthier, more measured conceptualization of agriculture, nutrition and diet. Tim Lang, in the UK, has also pointed out many other negative health and environmental effects of this system and some of the complexities involved in addressing it (Lang & Heasman, 2004; Lang et al, 2009).While it is tempting to say that buying at local farms and local markets and eating local produce will return us to an earlier era of consumption, this might be slightly naive. First and foremost, growing and eating locally is not efficient and has a large environmental footprint (Khan & Hanjra, 2009). Several studies have shown that the environmental cost of shipping small amounts over short distances is greater than that of shipping large amounts over long distances (Coley et al, 2009). Second, eating locally will not lower the prices or enable low-income consumers to purchase healthier foods. Finally, it is precisely the economies of scale that result from massive-scale production in areas with sufficient water and appropriate soil and other conditions that has allowed us to conquer hunger. Although many of us love to eat local food, this approach will not address global problems; local, small-scale farms simply cannot support the world population.The idea that animal products should form the basis of a ‘wealthy'' or ‘developed world'' diet has been scientifically debunked, but remains the social aspiration of billions of peopleThe produce sector will not be of much help either. The farming sectors that produce fruit, vegetables and beans are not well organized. This is related to the extensive funding provided to create the commodity organizations, such as the National Dairy Council, the National Cattlemen''s Beef Association, etc. These organizations created advertising campaigns such as the ‘Got Milk?'' milk moustache series, ‘Pork. The Other White Meat'', ‘The Incredible, Edible Egg'' and ‘Beef: It''s What''s for Dinner'' in the USA and globally to promote these commodities. They also lobby in other ways to support their business.Of course, agriculture is not the only problem; consumer demand is an equally important issue. We have created societies in the West that value and consume meat, dairy, poultry, fish and seafood. Over several generations, a particular way of life has been promoted and this has shifted expectations about diet to include large amounts of animal-sourced foods. The developing world wants to eat the same way and is rapidly increasing its demand for meat and other animal products (FAO, 2007).

Table 1

Past and projected meat and milk consumption in developing and developed countries

N and P colimitation of N2-fixing and N-supplied fynbos legumes from the Cape Floristic Region

Background and aims

Legume species in the fynbos vegetation of the Cape Floristic Region, that fix N₂ in soils with low P, may have evolved for enhanced acquisition and efficient use of P. It was hypothesized that N₂-fixing and combined-N supplied (N-supplied) A. linearis, P. calyptrata and C. genistoides are adapted to low P and would be relatively unresponsive to increased P of 100 μM.

Methods

18 legume species were evaluated for their nodulation response to low P availability. The N X P interaction was then examined in A. linearis, P. calyptrata and C. genistoides reliant on either N₂-fixation or 300 μM N (NH₄NO₃), and receiving 0.1, 1.0, 10 and 100 μM P (NaH₂PO₄).

Results

In the species selection experiment, A. linearis, P. calyptrata and C. genistoides, with the greatest nodule fresh weight (FW) and nodule FW to root FW ratio, were the most prolific nodulating species. In the N X P experiment, with low P supply, the biomass of N₂-fixing P. calyptrata and C. genistoides was consistently greater than that of N-supplied plants. In contrast, with high P supply of 100 μM P, all N-supplied plants accumulated more biomass than the corresponding N₂-fixing plants. High P-use efficiency, poor down-regulation of P uptake and P storage was evident in A. linearis and P. calyptrata.

Conclusion

The growth response to P and the significant N X P interactions indicate that N₂-fixing and N-supplied plants were not adapted to low P, but rather colimited by both N and P.     

The Neighborhood Energy Balance Equation: Does Neighborhood Food Retail Environment + Physical Activity Environment = Obesity? The CARDIA Study

Background

Recent obesity prevention initiatives focus on healthy neighborhood design, but most research examines neighborhood food retail and physical activity (PA) environments in isolation. We estimated joint, interactive, and cumulative impacts of neighborhood food retail and PA environment characteristics on body mass index (BMI) throughout early adulthood.

Methods and Findings

We used cohort data from the Coronary Artery Risk Development in Young Adults (CARDIA) Study [n=4,092; Year 7 (24-42 years, 1992-1993) followed over 5 exams through Year 25 (2010-2011); 12,921 person-exam observations], with linked time-varying geographic information system-derived neighborhood environment measures. Using regression with fixed effects for individuals, we modeled time-lagged BMI as a function of food and PA resource density (counts per population) and neighborhood development intensity (a composite density score). We controlled for neighborhood poverty, individual-level sociodemographics, and BMI in the prior exam; and included significant interactions between neighborhood measures and by sex. Using model coefficients, we simulated BMI reductions in response to single and combined neighborhood improvements. Simulated increase in supermarket density (from 25^th to 75^th percentile) predicted inter-exam reduction in BMI of 0.09 kg/m² [estimate (95% CI): -0.09 (-0.16, -0.02)]. Increasing commercial PA facility density predicted BMI reductions up to 0.22 kg/m² in men, with variation across other neighborhood features [estimate (95% CI) range: -0.14 (-0.29, 0.01) to -0.22 (-0.37, -0.08)]. Simultaneous increases in supermarket and commercial PA facility density predicted inter-exam BMI reductions up to 0.31 kg/m² in men [estimate (95% CI) range: -0.23 (-0.39, -0.06) to -0.31 (-0.47, -0.15)] but not women. Reduced fast food restaurant and convenience store density and increased public PA facility density and neighborhood development intensity did not predict reductions in BMI.

Conclusions

Findings suggest that improvements in neighborhood food retail or PA environments may accumulate to reduce BMI, but some neighborhood changes may be less beneficial to women.