Picks from PLoS Biology, PLoS Medicine, PLoS Neglected Tropical Diseases and PLoS ONE:
Preserving a Space for Science in an Age of Democracy:
How should scientific advice be incorporated into the political decisionmaking process? Even experts can't keep up with the torrent of studies published in their own field, and, supposedly, scientific issues--from climate change to biodiversity loss--have obvious political components. How is advice treated in an age when experts are increasingly viewed with suspicion and distrust?
The Paradox of Scientific Authority: The Role of Scientific Advice in Democracies, by Wiebe E Bijker, Roland Bal, and Ruud Hendriks, reveals the political decision-making in a study of the inner workings of the "Gezondheidsraad," a scientific advisory body to the Dutch government. Dutch officials invited Bijker et al. to observe the process and write their account, which was eventually presented to Queen Beatrix. So, it is one of those instances--these days growing in number--where the once-reviled sociologists are being asked to help the powerful understand the relationship between policy and science. The authors are well aware of the problems posed for their objectivity--both actual and perceived--by this dangerous shift from outsider to insider.
The Global Health System: Actors, Norms, and Expectations in Transition:
The global health system that evolved through the latter half of the 20th century achieved extraordinary success in controlling infectious diseases and reducing child mortality. Life expectancy in low- and middle-income countries increased at a rate of about 5 years every decade for the past 40 years [1]. Today, however, that system is in a state of profound transition. The need has rarely been greater to rethink how we endeavor to meet global health needs.
We present here a series of four papers on one dimension of the global health transition: its changing institutional arrangements. We define institutional arrangements broadly to include both the actors (individuals and/or organizations) that exert influence in global health and the norms and expectations that govern the relationships among them (see Box 1 for definitions of the terms used in this article).
Syphilis at the Crossroad of Phylogenetics and Paleopathology:
Syphilis is a reemerging disease burden. Although it has been studied for five centuries, its origin and spread is still controversial. Did it accompany the evolution of the genus Homo and does it date back to more than a million years or did it emerge only after Columbus's return to Europe? Initially, to test the validity of a new interdisciplinary approach we constructed a worldwide map showing precolumbian human skeletons with lesions of syphilis and other related diseases (also caused by different treponemes). Then, we selected the oldest cases to estimate the timing of the treponemes' history, using their DNA sequences and computer simulations. This resulted in treponeme evolutionary rates, and in temporal intervals during which these microorganisms could have emerged. Based on comparisons with other bacteria, we concluded that treponematoses did not emerge before our own species originated and that syphilis did not start affecting mankind only from 1492 onwards. Instead, it seems to have emerged in the time span between 16,500 and 5,000 years ago. Where syphilis emerged, however, remains unsolved. Finally, the endeavor of joining as distinct fields as paleopathology and molecular biology proved to be fruitful and promising to advance our understanding of the rise and fall of the infectious diseases that have afflicted humans across time and space.
Dissemination of Spotted Fever Rickettsia Agents in Europe by Migrating Birds:
Migratory birds are known to play a role as long-distance vectors for many microorganisms. To investigate whether this is true of rickettsial agents as well, we characterized tick infestation and gathered ticks from 13,260 migratory passerine birds in Sweden. A total of 1127 Ixodes spp. ticks were removed from these birds and the extracted DNA from 957 of them was available for analyses. The DNA was assayed for detection of Rickettsia spp. using real-time PCR, followed by DNA sequencing for species identification. Rickettsia spp. organisms were detected in 108 (11.3%) of the ticks. Rickettsia helvetica, a spotted fever rickettsia associated with human infections, was predominant among the PCR-positive samples. In 9 (0.8%) of the ticks, the partial sequences of 17kDa and ompB genes showed the greatest similarity to Rickettsia monacensis, an etiologic agent of Mediterranean spotted fever-like illness, previously described in southern Europe as well as to the Rickettsia sp.IrITA3 strain. For 15 (1.4%) of the ticks, the 17kDa, ompB, gltA and ompA genes showed the greatest similarity to Rickettsia sp. strain Davousti, Rickettsia japonica and Rickettsia heilongjiangensis, all closely phylogenetically related, the former previously found in Amblyomma tholloni ticks in Africa and previously not detected in Ixodes spp. ticks. The infestation prevalence of ticks infected with rickettsial organisms was four times higher among ground foraging birds than among other bird species, but the two groups were equally competent in transmitting Rickettsia species. The birds did not seem to serve as reservoir hosts for Rickettsia spp., but in one case it seems likely that the bird was rickettsiemic and that the ticks had acquired the bacteria from the blood of the bird. In conclusion, migratory passerine birds host epidemiologically important vector ticks and Rickettsia species and contribute to the geographic distribution of spotted fever rickettsial agents and their diseases.
Quiet and Poised: 'Silent' Genes Accumulate Transcription Machinery:
Gene activation--the process of waking up a silent gene and transcribing its DNA--requires many coordinated processes: the gene must be exposed to transcription factors, which must then pile onto specialized sequences adjacent to the gene-called enhancer and promoter regions, which then attract RNA polymerase (the enzyme that catalyzes the synthesis of messenger RNA), which can then attach and prepare to read the gene's sequence.
Within the nucleus, each chromosome sits in its own well-defined domain, called its territory. It has long been observed that activated genes relocate outside their chromosome's territory during expression, leading to the idea that this movement promotes activation by exposing the gene to the transcription machinery.
But is the opposite true? Do genes that remain in their territories have less access to RNA polymerase? It had been thought so, but a new study by Carmelo Ferrai, Sheila Xie, Ana Pombo, Massimo P. Crippa, and colleagues shows that even while sitting quietly within their home turf, some genes are already primed with the transcriptional machinery, poised and ready to go.
Are Patents Impeding Medical Care and Innovation?:
Background to the debate: Pharmaceutical and medical device manufacturers argue that the current patent system is crucial for stimulating research and development (R&D), leading to new products that improve medical care. The financial return on their investments that is afforded by patent protection, they claim, is an incentive toward innovation and reinvestment into further R&D. But this view has been challenged in recent years. Many commentators argue that patents are stifling biomedical research, for example by preventing researchers from accessing patented materials or methods they need for their studies. Patents have also been blamed for impeding medical care by raising prices of essential medicines, such as antiretroviral drugs, in poor countries. This debate examines whether and how patents are impeding health care and innovation.
Ulva prolifera, a common green seaweed, is one of the causative species of green tides that occurred frequently along the shores of Qingdao in 2008 and had detrimental effects on the preparations for the 2008 Beijing Olympic Games sailing competition, since more than 30 percent of the area of the games was invaded. In view of the rapid accumulation of the vast biomass of floating U. prolifera in green tides, we investigated the formation of sporangia in disks of different diameters excised from U. prolifera, changes of the photosynthetic properties of cells during sporangia formation, and development of spores. The results suggested that disks less than 1.00 mm in diameter were optimal for the formation of sporangia, but there was a small amount of spore release in these. The highest percentage of area of spore release occurred in disks that were 2.50 mm in diameter. In contrast, sporangia were formed only at the cut edges of larger disks (3.00 mm, 3.50 mm, and 4.00 mm in diameter). Additionally, the majority of spores liberated from the disks appeared vigorous and developed successfully into new individuals. These results implied that fragments of the appropriate size from the U. prolifera thalli broken by a variety of factors via producing spores gave rise to the rapid proliferation of the seaweed under field conditions, which may be one of the most important factors to the rapid accumulation of the vast biomass of U. prolifera in the green tide that occurred in Qingdao, 2008.
Suicide (self-inflicted death) is a major, preventable public-health problem. About 1 million people die each year from suicide and about 20 times as many people attempt suicide. Globally, suicide rates have increased by nearly a half over the past 45 years and suicide is now among the three leading causes of death in people aged 15-44 years. Within this age group, 1 in 20 deaths is a suicide. Most people who commit suicide have a mental illness, usually depression or substance abuse, but suicide can also be triggered by a stressful event such as losing a partner. Often warning signs are present--a person who talks about killing themselves must always be taken seriously. Adequate prevention and treatment of mental illness and interventions that teach young people coping skills and improve their self-esteem have shown promise in reducing suicide rates, as have strategies (for example, restrictions on the sale of pain killers) that reduce access to common methods of suicide.
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