Riviste scientifiche

Yields of peas grown exposed to an electric field generated by wind and rain were up 17.9 per cent, but is still remains unclear whether 'electroculture' really works

Astrophysicists hope a map created by the Dark Energy Spectroscopic Instrument will help answer questions about the expansion of the universe

A confident detection of a moon orbiting a planet beyond our solar system – called an exomoon – has eluded astronomers so far, but they have found a new candidate

The latest coronavirus news updated every day including coronavirus cases, the latest news, features and interviews from New Scientist and essential information about the covid-19 pandemic

Meat is responsible for roughly twice the greenhouse gas emissions of plant-based food. Can we afford not to seek alternative sources of protein for our food?

by Tingting Geng, Qi Lu, Zhenzhen Wan, Jingyu Guo, Liegang Liu, An Pan, Gang Liu

Background

Several epidemiological studies have suggested that vitamin D status is associated with risk of dementia in general populations. However, due to the synergistic effect between diabetic pathology and neuroinflammation, and the prothrombotic profile in patients with diabetes, whether vitamin D is associated with risk of dementia among patients with diabetes is unclear. This study aimed to investigate the associations of circulating vitamin D levels with risks of all-cause dementia, Alzheimer disease (AD), and vascular dementia (VD) among adults with type 2 diabetes (T2D).

Methods and findings

This study included 13,486 individuals (≥60 years) with T2D and free of dementia at recruitment (2006–2010) from the UK Biobank study. Serum 25-hydroxyvitamin D (25[OH]D) concentrations were measured using the chemiluminescent immunoassay method at recruitment. Serum 25(OH)D ≥ 75 nmol/L was considered sufficient, according to the Endocrine Society Clinical Practice Guidelines. Incidence of all-cause dementia, AD, and VD cases was ascertained using electronic health records (EHRs). Each participant’s person-years at risk were calculated from the date of recruitment to the date that dementia was reported, date of death, date of loss to follow-up, or 28 February 2018, whichever occurred first. Among the 13,486 individuals with T2D (mean age, 64.6 years; men, 64.3%), 38.3% had vitamin D ≥ 50 nmol/L and only 9.1% had vitamin D ≥ 75 nmol/L. During a mean follow-up of 8.5 years, we observed 283 cases of all-cause dementia, including 101 AD and 97 VD cases. Restricted cubic spline analysis demonstrated a nonlinear relationship between serum 25(OH)D and risk of all-cause dementia (Pnonlinearity < 0.001) and VD (Pnonlinearity = 0.007), and the nonlinear association reached borderline significance for AD (Pnonlinearity = 0.06), with a threshold at around a serum 25(OH)D value of 50 nmol/L for all the outcomes. Higher serum levels of 25(OH)D were significantly associated with a lower risk of all-cause dementia, AD, and VD. The multivariate hazard ratios and 95% confidence intervals for participants who had serum 25(OH)D ≥ 50 nmol/L, compared with those who were severely deficient (25[OH]D < 25 nmol/L), were 0.41 (0.29–0.60) for all-cause dementia (Ptrend < 0.001), 0.50 (0.27–0.92) for AD (Ptrend = 0.06), and 0.41 (0.22–0.77) for VD (Ptrend = 0.01). The main limitation of the current analysis was the potential underreporting of dementia cases, as the cases were identified via EHRs.

Conclusions

In this study, we observed that higher concentrations of serum 25(OH)D were significantly associated with a lower risk of all-cause dementia, AD, and VD among individuals with T2D. Our findings, if confirmed by replication, may have relevance for dementia prevention strategies that target improving or maintaining serum vitamin D concentrations among patients with T2D.

by Si-Yeung Yu, Mary Sau-Man Ip, Xue Li, Ka-Shing Cheung, Qing-Wen Ren, Mei-Zhen Wu, Hang-Long Li, Pui-Fai Wong, Hung-Fat Tse, Kai-Hang Yiu

Background

Evidence suggests that chronic obstructive pulmonary disease (COPD) is associated with a higher risk of lung carcinoma. Using a territory-wide clinical electronic medical records system, we investigated the association between low-dose aspirin use (≤160 mg) among patients with COPD and incidence of lung carcinoma and the corresponding risk of bleeding.

Methods and findings

This is a retrospective cohort study conducted utilizing Clinical Data Analysis Reporting System (CDARS), a territory-wide database developed by the Hong Kong Hospital Authority. Inverse probability of treatment weighting (IPTW) was used to balance baseline covariates between aspirin nonusers (35,049 patients) with new aspirin users (7,679 patients) among all eligible COPD patients from 2005 to 2018 attending any public hospitals. The median age of the cohort was 75.7 years (SD = 11.5), and 80.3% were male. Competing risk regression with Cox proportional hazards model were performed to estimate the subdistribution hazard ratio (SHR) of lung carcinoma with low-dose aspirin and the associated bleeding events. Of all eligible patients, 1,779 (4.2%, 1,526 and 253 among nonusers and users) were diagnosed with lung carcinoma over a median follow-up period of 2.6 years (interquartile range [IQR]: 1.4 to 4.8). Aspirin use was associated with a 25% lower risk of lung carcinoma (SHR = 0.75, 95% confidence interval [CI] 0.65 to 0.87, p = <0.001) and 26% decrease in lung carcinoma–related mortality (SHR = 0.74, 95% CI 0.64 to 0.86, p = <0.001). Subgroup analysis revealed that aspirin was beneficial for patients aged above or below 75 years, but was also beneficial among populations who were male, nondiabetic, and nonhypertensive. Aspirin use was not associated with an increased risk of upper gastrointestinal bleeding (UGIB) (SHR = 1.19, 95% CI 0.94 to 1.53, p = 0.16), but was associated with an increased risk of hemoptysis (SHR = 1.96, 95% CI 1.73 to 2.23, p < 0.001). The main limitations of the study were (i) that one group of patients may be more likely to seek additional medical attention, although this was partially mitigated by the use of propensity score analysis; and (ii) the observational nature of the study renders it unable to establish causality between aspirin use and lung carcinoma incidence.

Conclusions

In this study, we observed that low-dose aspirin use was associated with a lower risk of lung carcinoma and lung carcinoma–related mortality among COPD patients. While aspirin was not associated with an increased risk of UGIB, the risk of hemoptysis was elevated.

by Paolo Rodi, Werner Obermeyer, Ariel Pablos-Mendez, Andrea Gori, Mario C. Raviglione

Background

Recognising the substantial political weight of the United Nations General Assembly (UNGA), a UN General Assembly special session (UNGASS) and high-level meetings (HLMs) have been pursued and held for 5 health-related topics thus far. They have focused on human immunodeficiency virus/acquired immune deficiency syndrome (HIV/AIDS, 2001), non-communicable diseases (NCDs, 2011), antimicrobial resistance (AMR, 2016), tuberculosis (TB, 2018), and universal health coverage (UHC, 2019). This observational study presents a comprehensive analysis of the political and policy background that prompted the events, as well as an assessment of aims, approaches, and ultimate outcomes.

Methods and findings

We investigated relevant agencies’ official documents, performed a literature search, and accessed international institutions’ websites for the period 1990–2020. Knowledgeable diplomatic staff and experts provided additional information. Outcomes were evaluated from a United Nations perspective based on national and international commitments, and funding trends. Eliciting an effective governmental response through UNGASSs/HLMs is a challenge. However, increased international commitment was evident after the HIV/AIDS (2001), NCDs (2011), and AMR (2016) meetings. The more recent TB (2018) and UHC (2019) HLMs have received general endorsements internationally, although concrete commitments are not yet documented. Although attribution can only be hypothesized, financial investments for HIV/AIDS following the UNGASS were remarkable, whereas following HLMs for NCDs, AMR, and TB, the financial investments remained insufficient to face the burden of these threats. Thus far, the HIV/AIDS UNGASS was the only one followed by a level of commitment that has likely contributed to the reversal of the previous burden trend. Limitations of this study include its global perspective and aerial view that cannot discern the effects at the country level. Additionally, possible peculiarities that modified the response to the meetings were not looked at in detail. Finally, we assessed a small sample of events; thus, the list of strategic characteristics for success is not exhaustive.

Conclusions

Overall, UNGASSs and HLMs have the potential to lay better foundations and boldly address key health challenges. However, to succeed, they need to (i) be backed by large consensus; (ii) engage UN authorities and high-level bodies; (iii) emphasise implications for international security and the world economy; (iv) be supported by the civil society, activists, and champions; and (v) produce a political declaration containing specific, measurable, achievable, relevant, and time-bound (SMART) targets. Therefore, to ensure impact on health challenges, in addition to working with the World Health Assembly and health ministries, engaging the higher political level represented by the UNGA and heads of state and government is critical.

A device that delivers electric current to the knees could help combat osteoarthritis, a painful condition caused by worn cartilage, after successful tests in rabbits

Meteor showers leave clues to their origin in their wake and you can help astronomers unravel the mystery by taking part in the Radio Meteor Zoo project, says Layal Liverpool

Hints of a fifth force of nature may only interest researchers and science lovers for now, but physics breakthroughs have a habit of delivering technological leaps

Space colonies offer rich people a way off a broken Earth in Tochi Onyebuchi's latest sci-fi novel, but the pull of home is a powerful force, says Sally Adee

Traits like conscientiousness or extroversion might seem to define your character, but these aren't set in stone and new research reveals how anyone can change their personality - if they really want to

New Scientist's weekly round-up of the best books, films, TV series, games and more that you shouldn't miss

Sign languages are flourishing in many parts of the world. This could bring cognitive benefits for all who learn them, says Bencie Woll

The universe is filled with so much more matter than antimatter. The LEGEND experiment, photographed by Enrico Sacchetti, will soon start trying to unravel this conundrum

Leonard Mlodinow's book Emotional argues that our feelings are a key tool in our intellectual arsenal, rather than the Achilles' heel of rational thought that they are often made out to be

Keen to gain an edge for the day ahead? A secular ritual really can bring greater success even for rational thinkers, writes David Robson

Around 23 million years ago, North America's sabre-toothed cat-like animals disappeared, leaving the continent without felines for several million years. Now palaeontologists are solving the mystery of this "Cat Gap"

The little rodents can drink without falling off their wheels, while the large beasts go on a rampage. Plus more nominative determinism and some elementary names, in Feedback’s weekly instalment