Riviste scientifiche

[Correspondence] Teriparatide vs risedronate for osteoporosis – Authors' reply

The Lancet - Sa, 12/05/2018 - 00:00
Yair Liel stated that the VERO clinical trial1 results were of relatively minor clinical significance because of the nature of the active comparator used (risedronate) and because bone turnover markers were not measured, suggesting that the inferior anti-fracture efficacy in the risedronate group was not evaluated properly. He suggested that a clinically relevant comparison could be made between teriparatide and zoledronate, or between teriparatide and denosumab, given their superior effects on bone mineral density observed when compared with oral bisphosphonates.

Distributional change of women’s adult height in low- and middle-income countries over the past half century: An observational study using cross-sectional survey data

PLoS Medicine - Ve, 11/05/2018 - 23:00

by Jewel Gausman, Ivan Meija Guevara, S. V. Subramanian, Fahad Razak

Background

Adult height reflects childhood circumstances and is associated with health, longevity, and maternal–fetal outcomes. Mean height is an important population metric, and declines in height have occurred in several low- and middle-income countries, especially in Africa, over the last several decades. This study examines changes at the population level in the distribution of height over time across a broad range of low- and middle-income countries during the past half century.

Methods and findings

The study population comprised 1,122,845 women aged 25–49 years from 59 countries with women’s height measures available from four 10-year birth cohorts from 1950 to 1989 using data from the Demographic and Health Surveys (DHS) collected between 1993 and 2013. Multilevel regression models were used to examine the association between (1) mean height and standard deviation (SD) of height (a population-level measure of inequality) and (2) median height and the 5th and 95th percentiles of height. Mean-difference plots were used to conduct a graphical analysis of shifts in the distribution within countries over time. Overall, 26 countries experienced a significant increase, 26 experienced no significant change, and 7 experienced a significant decline in mean height between the first and last birth cohorts. Rwanda experienced the greatest loss in height (−1.4 cm, 95% CI: −1.84 cm, −0.96 cm) while Colombia experienced the greatest gain in height (2.6 cm, 95% CI: 2.36 cm, 2.84 cm). Between 1950 and 1989, 24 out of 59 countries experienced a significant change in the SD of women’s height, with increased SD in 7 countries—all of which are located in sub-Saharan Africa. The distribution of women’s height has not stayed constant across successive birth cohorts, and regression models suggest there is no evidence of a significant relationship between mean height and the SD of height (β = 0.015 cm, 95% CI: −0.032 cm, 0.061 cm), while there is evidence for a positive association between median height and the 5th percentile (β = 0.915 cm, 95% CI: 0.820 cm, 1.002 cm) and 95th percentile (β = 0.995 cm, 95% CI: 0.925 cm, 1.066 cm) of height. Benin experienced the largest relative expansion in the distribution of height. In Benin, the ratio of variance between the latest and earliest cohort is estimated as 1.5 (95% CI: 1.4, 1.6), while Lesotho and Uganda experienced the greatest relative contraction of the distribution, with the ratio of variance between the latest and earliest cohort estimated as 0.8 (95% CI: 0.7, 0.9) in both countries. Limitations of the study include the representativeness of DHS surveys over time, age-related height loss, and consistency in the measurement of height between surveys.

Conclusions

The findings of this study indicate that the population-level distribution of women’s height does not stay constant in relation to mean changes. Because using mean height as a summary population measure does not capture broader distributional changes, overreliance on the mean may lead investigators to underestimate disparities in the distribution of environmental and nutritional determinants of health.

Towing icebergs to Cape Town is a poor way to halt water crisis

New Scientist - Ve, 11/05/2018 - 20:00
Hauling chunks of polar ice to dry regions to provide fresh water sounds tempting but there are many reasons to reject it, says Olive Heffernan

Utterly bizarre theoretical ‘fractons’ could be made for real

New Scientist - Ve, 11/05/2018 - 17:19
A fracton is a weird imaginary half-particle, and can only move when paired with another fracton. It sounds wild but we could make one in a crystal

Measles cases in England are up 65 per cent on last year

New Scientist - Ve, 11/05/2018 - 14:03
There have been 440 confirmed cases of measles in England so far this year. These cases are linked to ongoing outbreaks in Europe, according to Public Health England

Trolley problem tested in real life for first time with mice

New Scientist - Ve, 11/05/2018 - 13:40
Would you kill someone to save five others? The first lab enactment of this classic thought experiment raises issues for how we programme self-driving cars

Stem cells may reveal how Neanderthal DNA works in modern humans

New Scientist - Ve, 11/05/2018 - 11:00
Many of us carry DNA inherited from Neanderthals, but we can’t be sure how it affects us. Stem cells with Neanderthal DNA could tell us

Napoleon Complex: Are smaller men really more aggressive?

New Scientist - Ve, 11/05/2018 - 08:00
A study investigating short-man syndrome suggests that smaller men may behave more aggressively than others, providing there are no likely repercussions

[Articles] International validation of the consensus Immunoscore for the classification of colon cancer: a prognostic and accuracy study

The Lancet - Ve, 11/05/2018 - 00:30
The Immunoscore provides a reliable estimate of the risk of recurrence in patients with colon cancer. These results support the implementation of the consensus Immunoscore as a new component of a TNM-Immune classification of cancer.

[Comment] Immunoscore for (colorectal) cancer precision medicine

The Lancet - Ve, 11/05/2018 - 00:30
Immunotherapies targeting immune checkpoints such as CTLA4, PDCD1 (PD-1), and CD274 (PD-L1) have revolutionised oncology.1 High-level microsatellite instability (MSI-high) caused by mismatch repair deficiency is routinely used as a biomarker to predict response to immune-checkpoint blockade.2 MSI-high status in colorectal carcinoma correlates with tumour neoantigen loads, which in turn correlate with immune response.3 Combined analysis of tumoural and immune factors (eg, the so-called Tumour Immunity in the MicroEnvironment [TIME] classification) could be a new cancer classification system.

Satellite images reveal how powerful North Korea’s nukes are

New Scientist - Gi, 10/05/2018 - 21:00
Studying pictures of North Korea's nuclear test site has let researchers calculate its weapons are about 10 times more powerful than the bomb dropped on Hiroshima

A plague from South Korea is killing frogs and toads worldwide

New Scientist - Gi, 10/05/2018 - 21:00
The world’s amphibians are dying in swathes because of the lethal chytrid fungus, and it seems the epidemic had its origins on the Korean peninsula

Interstellar cloud mapped by listening to its magnetic waves

New Scientist - Gi, 10/05/2018 - 21:00
Magnetic waves vibrating through an interstellar cloud called Musca reveal its 3D shape. We though it was long and thin, but it’s actually flat like a pancake

Captain Cook: The farmer’s son who re-drew the map of the world

New Scientist - Gi, 10/05/2018 - 20:00
The achievements of the eighteenth-century explorer stand up surprisingly well to modern scrutiny, finds Boyd Tonkin

Eating all your meals before 3pm could be good for your health

New Scientist - Gi, 10/05/2018 - 18:00
Eating all of your daily meals by mid-afternoon has been found to lower appetite and cut blood pressure, and may make you less likely to develop diabetes

Tourism is four times worse for the climate than we thought

New Scientist - Gi, 10/05/2018 - 17:45
Tourism is being blamed for 8 per cent of greenhouse gas emissions, and it emits more every year – making it harder to stop dangerous climate change

Hope for herpes vaccine after it wipes out virus in monkeys

New Scientist - Gi, 10/05/2018 - 17:00
Animal trials have proved successful in preventing and treating genital herpes in guinea pigs and monkeys, giving hope that the vaccine will move into human trials within the year

Eye scanner can tell if you’ve mastered a foreign language

New Scientist - Gi, 10/05/2018 - 16:19
By monitoring unconscious eye movements while reading, an algorithm can predict the proficiency of someone learning English as a second language

China is building a huge weather-control machine – will it work?

New Scientist - Me, 09/05/2018 - 20:00
Water shortages are a huge problem for Chinese agriculture, so the country has just begun the world's largest ever weather control experiment

DeepMind AI developed navigation neurons to solve a maze like us

New Scientist - Me, 09/05/2018 - 20:00
Humans have neurons called “grid cells” that help us find our way as we navigate our surroundings. DeepMind's AI has developed something similar as it learned to navigate a maze
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