Riviste scientifiche

How besieged ants decide when it’s time to abandon their nests

New Scientist - Ve, 05/01/2018 - 17:20
Colonies of turtle ants are often attacked by competing species, and the ants understand enough military strategy to decide when certain nests should be abandoned

Baby skeleton from Alaska reveals origins of Native Americans

New Scientist - Ve, 05/01/2018 - 15:12
DNA from an infant girl who died 11,500 years ago reveals where America’s first human settlers came from and when they arrived

Your computer may run 30 per cent slower due to Intel chip bug

New Scientist - Ve, 05/01/2018 - 13:30
The details of a massive issue with Intel chips built over the last decade are slowly being revealed in what could be the biggest security flaw of the century

A daily blast of sound and electrical pulses may tame tinnitus

New Scientist - Ve, 05/01/2018 - 12:00
A new technique to tackle the phantom noises of tinnitus brought total relief for some patients and eased symptoms in half those who tried it

Association between intake of less-healthy foods defined by the United Kingdom's nutrient profile model and cardiovascular disease: A population-based cohort study

PLoS Medicine - Gi, 04/01/2018 - 23:00

by Oliver T. Mytton, Nita G. Forouhi, Peter Scarborough, Marleen Lentjes, Robert Luben, Mike Rayner, Kay Tee Khaw, Nicholas J. Wareham, Pablo Monsivais

Background

In the United Kingdom, the Food Standards Agency-Ofcom nutrient profiling model (FSA-Ofcom model) is used to define less-healthy foods that cannot be advertised to children. However, there has been limited investigation of whether less-healthy foods defined by this model are associated with prospective health outcomes. The objective of this study was to test whether consumption of less-healthy food as defined by the FSA-Ofcom model is associated with cardiovascular disease (CVD).

Methods and findings

We used data from the European Prospective Investigation of Cancer (EPIC)-Norfolk cohort study in adults (n = 25,639) aged 40–79 years who completed a 7-day diet diary between 1993 and 1997. Incident CVD (primary outcome), cardiovascular mortality, and all-cause mortality (secondary outcomes) were identified using record linkage to hospital admissions data and death certificates up to 31 March 2015. Each food and beverage item reported was coded and given a continuous score, using the FSA-Ofcom model, based on the consumption of energy; saturated fat; total sugar; sodium; nonsoluble fibre; protein; and fruits, vegetables, and nuts. Items were classified as less-healthy using Ofcom regulation thresholds. We used Cox proportional hazards regression to test for an association between consumption of less-healthy food and incident CVD. Sensitivity analyses explored whether the results differed based on the definition of the exposure. Analyses were adjusted for age, sex, behavioural risk factors, clinical risk factors, and socioeconomic status. Participants were followed up for a mean of 16.4 years. During follow-up, there were 4,965 incident cases of CVD (1,524 fatal within 30 days). In the unadjusted analyses, we observed an association between consumption of less-healthy food and incident CVD (test for linear trend over quintile groups, p < 0.01). After adjustment for covariates (sociodemographic, behavioural, and indices of cardiovascular risk), we found no association between consumption of less-healthy food and incident CVD (p = 0.84) or cardiovascular mortality (p = 0.90), but there was an association between consumption of less-healthy food and all-cause mortality (test for linear trend, p = 0.006; quintile group 5, highest consumption of less-healthy food, versus quintile group 1, HR = 1.11, 95% CI 1.02–1.20). Sensitivity analyses produced similar results. The study is observational and relies on self-report of dietary consumption. Despite adjustment for known and reported confounders, residual confounding is possible.

Conclusions

After adjustment for potential confounding factors, no significant association between consumption of less-healthy food (as classified by the FSA-Ofcom model) and CVD was observed in this study. This suggests, in the UK setting, that the FSA-Ofcom model is not consistently discriminating among foods with respect to their association with CVD. More studies are needed to understand better the relationship between consumption of less-healthy food, defined by the FSA-Ofcom model, and indices of health.

‘Thrill-seeking’ genes could help birds escape climate change

New Scientist - Gi, 04/01/2018 - 20:00
Some birds may escape extinction if their genes favour exploring newer, more hospitable habitats

The universe could be full of more huge stars than we thought

New Scientist - Gi, 04/01/2018 - 20:00
Part of the Large Magellanic Cloud has 32 per cent more giant stars than we expected. That could mean the universe has more supernovae and black holes, too

Opioids that hit different brain target could be less addictive

New Scientist - Gi, 04/01/2018 - 18:00
Researchers have determined how morphine derivatives bind to the kappa opioid receptor, which should enable safer painkillers to be developed

Iconic tree from Twin Peaks threatened by climate change

New Scientist - Gi, 04/01/2018 - 15:56
The Douglas fir is one of the most ecologically and economically vital species in the Pacific Northwest, but global warming may pose a serious threat to it

SpaceX Falcon Heavy rocket test is the start of a race to Mars

New Scientist - Gi, 04/01/2018 - 14:05
The imminent first flight of Elon Musk's giant new rocket could mark a spectacular start to a new era in space flight, says Paul Marks

Largest prime number ever found has over 23 million digits

New Scientist - Gi, 04/01/2018 - 12:38
Two multiplied by itself nearly eighty million times minus one is the biggest prime number ever discovered by the Great Internet Mersenne Prime Search

A new bitcoin Ponzi scheme or scam pops up almost every day

New Scientist - Gi, 04/01/2018 - 11:44
Everyone seems to be investing in bitcoin, but it can be a financial minefield. Now researchers have shown that new scams are popping up every day

Tides and atmospheres on TRAPPIST-1 planets may help life thrive

New Scientist - Me, 03/01/2018 - 21:57
The planets of the TRAPPIST-1 system could be complex worlds with volcanoes, atmospheres and warm subsurface oceans. Some might even be able to host life

NHS is switching to cheaper mimics of expensive cancer drugs

New Scientist - Me, 03/01/2018 - 19:00
Biological drugs like some antibodies used to fight cancer are difficult to make. The NHS is now turning to cheaper alternatives, but some doctors fear they won’t work as well

China’s plan to stop recycling the world’s rubbish may backfire

New Scientist - Me, 03/01/2018 - 19:00
China is giving Western nations a headache with a ban on imports of "foreign garbage" to recycle, but the move is also creating a Chinese cardboard shortage

Weird dim star isn’t due to alien megastructure – it’s just dust

New Scientist - Me, 03/01/2018 - 16:58
Tabby’s star flickers like no other star we’ve seen. Some have suggested that’s due to an alien structure blocking its light, but it’s likely just dust

Can listening to a low hum destroy Alzheimer’s brain plaques?

New Scientist - Me, 03/01/2018 - 15:00
Flickering light, low sounds and vibrating pads are all being tried out in people with Alzheimer’s after promising research in mice

Blood test spots ovarian cancer years before it is usually found

New Scientist - Me, 03/01/2018 - 12:16
A blood test that detects ovarian cancer up to two years earlier than is presently the case could help reduce the deadliness of the disease

2018 preview: Quantum computers to overtake ordinary machines

New Scientist - Me, 03/01/2018 - 11:30
The quantum computing era is upon us. Google is building up to a breakthrough on par with the launch of Sputnik or the splitting of the atom

Pelvic inflammatory disease risk following negative results from chlamydia nucleic acid amplification tests (NAATs) versus non-NAATs in Denmark: A retrospective cohort

PLoS Medicine - Ma, 02/01/2018 - 23:00

by Bethan Davies, Katy M. E. Turner, Thomas Benfield, Maria Frølund, Berit Andersen, Henrik Westh, on behalf of the Danish Chlamydia Study , Helen Ward

Background

Nucleic Acid Amplification Tests (NAATs) are the recommended test type for diagnosing Chlamydia trachomatis (chlamydia). However, less sensitive diagnostic methods—including direct immunofluorescence (IF) and enzyme-linked immunoassay (ELISA)—remain in use in lower resourced settings. We estimate the risk of pelvic inflammatory disease (PID) following undiagnosed infection in women tested with non-NAATs and estimate the health gain from using accurate diagnostic tests.

Methods and findings

We used Denmark’s national Chlamydia Study dataset to extract all chlamydia tests performed in women aged 15–34 years (1998–2001). Tests were categorised as non-NAAT (IF/ELISA) or NAAT and limited to each woman’s first test in the study period. We linked test data to hospital presentations for PID within 12 months from the Danish National Patient Register. The study included 272,105 women with a chlamydia test, just under half (44.78%, n = 121,857) were tested using NAATs. Overall, 6.38% (n = 17,353) tested positive for chlamydia and 0.64% (n = 1,732) were diagnosed with PID within 12 months. The risk of PID following a positive chlamydia test did not differ by test type (NAAT 0.81% [95% CI 0.61–1.00], non-NAAT 0.78% [0.59–0.96]). The risk of PID following a negative test was significantly lower in women tested with NAATs compared to non-NAATs (0.55% [0.51–0.59] compared to 0.69% [0.64–0.73]; adjusted odds ratio (AOR) 0.83 [0.75–0.93]). We estimate that 18% of chlamydia infections in women tested with a non-NAAT were undiagnosed and that the risk of progression from undiagnosed chlamydia infection to PID within 12 months was 9.52% (9.30–9.68). Using non-NAATs could lead to an excess 120 cases of PID per 100,000 women tested compared to using NAATs. The key limitations of this study are under ascertainment of PID cases, misclassification bias in chlamydia and PID exposure status, bias to the association between clinical presentation and test type and the presence of unmeasured confounders (including other sexually transmitted infection [STI] diagnoses and clinical indication for chlamydia test).

Conclusion

This retrospective observational study estimates the positive impact on women’s reproductive health from using accurate chlamydia diagnostic tests and provides further evidence for restricting the use of inferior tests. Women with a negative chlamydia test have a 17% higher adjusted risk of PID by 12 months if they are tested using a non-NAAT compared to a NAAT.

Condividi contenuti